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1. 1 10 File Naming Conventions 1 10 USING THE eShell PROGRAM 1 11 Gettihg Started Rex RR UU wa EE es 1 11 Online HELP zog ru ee io omi ende ic End etal eee 1 11 Accessing Databases 22e 1 12 eQL Command Entry 1 13 Symbol Substitutions 1 15 DATABASE PROTECTION sss ee 1 16 DATABASE INTEGRITY 5 8 aca 8 hae RES I Ye vod oou Rp ve 1 17 WORKING WITH MULTIPLE DATABASES 1 17 MOVING DATABASES BETWEEN COMPUTERS 1 17 eshell LIMITATIONS i sudo eee fae dale eae gue Goal Rll PR oes 1 17 Reserved Words 2 1 17 Size Limitations 4 ed ded V eM A te ks e bd epe d 1 18 USING THE TUTORIAL 5 op ER PAG eese ae dla RUE RU 1 18 2 DIRECTORIES AND ENTITIES REFERENCING DIRECTORIES IN COMMANDS 2 1 CREATING DIRECTORIES 2 2 THE WORKING DIRECTORY llle ss ss 2 2 REMOVING DIRECTORIES ee 2 3 LISTING DIRECTORIES sse les 2 3 Using a Path Specification 2 3 TheEntity Directory uo goes mm x eeu Rege Rd ew Repub 2 5 DESCRIBING DATABA
2. FUNCTION PURPOSE ALLOWED INPUT TYPES INT RSP RDP CSP CDP ABS x Absolute value a a a a ACOS x Inverse trigonometric cosine a ASIN x Inverse trigonometric sine a ATAN x Inverse trigonometric tangent CMPLX x y Convert to CSP E E E COS x Trigonometric sine E E a COSH x Hyperbolic cosine a a DCMPLX x y Convert to CDP L DBLE x Convert to RDP Exponential function INT x Convert to INT LOG Natural base e logarithm LOG10 x Common base 10 logarithm E E E MOD x Remainder REAL x Convert to RSP a E SIN x Trigonometric sine a a E SINH x Hyperbolic sine SQRT x Square root E E E Trigonometric tangent Hyperbolic tangent E H Example 4 10 List the grid point identification numbers and the dis tance that the grid point is from the origin for grid points having Y coordinates of 1 0 eSh SELECT GID SORT X 2 Y 2 Z 2 FROM GRID 2 gt WHERE Y 1 0 GID SORT X 2 Y 24 Z 2 00000 00 41421 00 23607 00 16228 00 12311 00 5 Entries Selected RETRIEVING DATA FROM RELATIONS 4 7 User s Manual THE JOIN OPERATION 4 8 eShell Note that the column label is identified by the actual equation used to define the virtual attribute and the field
3. Shape SYMMETRIC Number of Rows 6 Number of Columns 6 Density 0 44 RELATION GEOM GRID GID CID X Y Z 1 0 0 0 140 0 0 2 0 1 0 1 0 0 0 3 0 2 0 1 0 0 0 4 0 30 1 0 0 0 5 0 4 0 1 0 0 0 6 0 0 0 0 0 0 0 7 0 1 0 0 0 0 0 8 0 2 0 0 0 0 0 9 0 350 0 0 0 0 10 0 4 0 0 0 0 0 RELATION RESULT Q4STR 1 EID SIGX SIGY TAUXY 1 1 0 6 2 0 6 4 0 4 2 3 0 6 1 0 7 6 0 3 2 0 6 3 0 6 4 0 4 4 2 0 6 1 0 6 5 0 4 RELATION RESULT Q4S EID CASE SIGX SIGY TAUXY 1 1 1 046 2 0 6 4 0 4 2 1 3 06 L 047 6 043 3 2 0 6 3 0 6 4 0 4 4 1 2 0 6 1 046 5 044 i 2 7 07 0 0 Bs DED 2 2 6 0 7 0 0 2 0 3 3 2 S 0 0 1 044 4 2 4 07 0 0 4 043 STREAM MODEL STRM Numeric Type INT Length 1000 1 20 FREEFORM MO DEL TESTFREE Numeric Type RSP Number of Records 5 Longest Record 50 FOR DIRECTORY PLOT You Must Query the Database INTRODUCTION eShell Users Manual 2 DIRECTORIES AND ENTITIES As introduced in Chapter 1 an eBase database may be logically config ured using a hierarchical structure of Directories This Chapter describes the commands which you may use to manipulate and manage a direc tory structure and those used to describe the entities within the directory structure REFERENCING DIRECTORIES IN COMMANDS When you use a hierarchical set of directories
4. COPY MODEL TESTFREE TO INS FREE 1 Entity Copied INSERT INTO FREEFORM INS FREE VALUES 100 200 300 400 500 Record Added to TESTEB TUTOR INS FREE FREEFORM SELECT FROM INS FREE WHERE RECORDS IN 6 Single Precision 6 Records 50 Data Values in Longest Record 6 5 Data Values 100 0 200 0 300 0 400 0 500 0 The WRITE privilege is also required to INSERT new data into Freeform entities When you INSERT into a Freeform entity with Records the new Record automatically becomes Record 1 8 4 INSERTING DATA INTO ENTITIES eShell Users Manual ADDING DATA VALUES TO STREAM ENTITIES Additional Data Values beyond those existing in a Schematic Stream entity may be inserted using command INSERT INTO STREAM stream name VALUES value list The value list will be inserted into the Freeform entity stream name beginning at the next available position that is one posi tion beyond the last Data Value in the entity As with Schematic Freeform entities all of the Data Values must be conformable to the correct Nu meric Type for Schematic Stream entities Example 8 6 Copy the Stream entity STRM to INS STRM add 3 new Data Values and verify the result eSh COPY MODEL STRM TO INS STRM Entity Copied eSh gt INSERT INTO STREAM INS STRM 25 VALUES 1001 1002 1003 3 Data Values Added to TESTEB TUTOR INS STRM eSh STREAM SELECT 1001 1002 1003 FROM INS STRM Integer 1003
5. 1 4 Chapter 4 Retrieving Data from RELATIONS 1 5 Chapter 5 Graphing Retrieved 1 6 Chapter 6 Indexing Relational Entities 1 7 Chapter 7 Retrieving Data from Non Relational Entities 1 8 Chapter 8 Inserting Data into Entities 1 9 Chapter 9 Updating Data 1 9 Chapter 10 Removing 1 1 10 Chapter 11 File Environment Commands 00 000000 eee 1 10 Chapter 12 Report Generation 1 11 Chapter 13 Utility 1 13 B GDLOSSABUY etu n dee i is ee a ee a t a ORI ees ata Be Qe eoe TUR ox B 1 INDEX ok e od eren Le ok t Eo ee ORC Index 1 TABLE OF CONTENTS v User s Manual vi This pageis intentionally blank eShell TABLE OF CONTENTS eShell Users Manual 1 INTRODUCTION The Engineering Database Management System eBase developed by Universal Analytics Inc UAI provides an advanced data management facility for scientific software applications development The design of the database allows its effective use in structuring and managing any large collection of engineering data The Interactive eBase Shell eShell is a separate computer program that allows the d
6. If an ORDER part is used with a GROUP part then the sorting opera tion is performed separately on each group created as illustrated in the next example RETRIEVING DATA FROM RELATIONS eShell Users Manual Example 4 17 Repeat example 4 13 ordering the resulting stresses in de scending order eSh gt SELECT QUAD4 PID Q4STR SIGX 2 gt FROM QUAD4 RESULT Q4STR 1 3 gt WHERE QUAD4 EID Q4STR EID GROUP BY QUAD4 PID ORDER BY 2 DESC MAX SIGX 3 00000 06 2 00000 06 2 Entries Selected THE SUBQUERY One of the most powerful aspects of the eQL language is its provision for subqueries to appear in SELECT commands A Subquery is simply a com plete SELECT that is used in the WHERE part of another query com mand Consider the following example Example 4 18 Determine the thickness of QUAD4 element EID 4 by first determining its property identification number PID and then finding the thickness used by elements with that property from Relation PSHELL SELECT PID FROM QUAD4 WHERE EID 4 1 Entry Selected SELECT T FROM MODEL PSHELL WHERE PID 2 5 00000E 01 1 Entry Selected Note that in this case the result of the first query was used to determine the selection criteria for the second The same result may be obtained by using a subquery Example 4 19 Determine the same information as in Example 4 16 us ing a single query with a subquery in the WHERE part eSh SELECT T FROM MODE
7. 1 m j 1 n SQUARE Aij i 1 n j 1 0 shape SYMMETRIC Aij Aji i 1 n j 1 n DIAGONAL Aij 0 when i j IDENTITY 1 0 Aij 0 when i CREATING eBase ENTITIES eShell Users Manual Example 3 3 Create Matrix NEWKGG in directory TUTOR with the same characteristics as KGG on the TESTEB database eSh CD MODEL eSh CREATE MATRIX NEWKGG 2 MODE COMPRESS 3 TYPE RDP 4 SHAPE SYMMETRIC 5 ROWS 6 Or eSh CREATE MATRIX MODEL NEWKGG LIKE KGG CREATING FREEFORM ENTITIES CREATING eBase ENTITIES New Freeform entities may be created as long as they are Schematic Recall from Chapter 1 that this means they must have a homogeneous data type You create a Freeform with the command CREATE FREEFORM free name TYPE num type LIKE old free name where the ree name is the entity name Each Freeform entity has a single characteristic its Numeric Type num type The allowable values are shown in Table 3 3 Again ADMINISTRATION privilege is required to create these entities and the LIKE clause may be specified to use the attributes of an existing entity I Example 3 4 Create Freeform NEW FREE in directory TUTOR with the same characteristics as FREE on the TESTEB database CD TUTOR CREATE FREEFORM NEW FREE TYPE RDP Or CREATE FREEFORM NEW FREE LIKE MODEL FREE Table 3 3
8. Notice that an asterisk marks the current position within the active command You execute the active command by entering RUN The RUN command is typically invoked after modifying or correcting the previous command One last feature of command entry is the blank or null line entry If you discover that your command is in error prior to entering the semicolon you may enter a blank line at the prompt This closes command input activity and allows you to edit the command im mediately At the end of a session you enter the eQL command INTRODUCTION eShell Users Manual END This command closes all the active databases provides a summary of computer resources that were used during the session and returns to the operating system of the host computer Symbol Substitutions INTRODUCTION You may at any time during your eShell session define symbols which may be used in subsequent commands Symbols are defined using the command DEFINE symbol value The symbol name must contain 32 or fewer characters and begin with a letter The value is used to set the symbol It is always treated as a simple character string which will be substituted for appearances of the symbol To use a symbol you use the substitution notation illustrated in the previous section amp symbol name If a symbol that you reference has not been defined you will be prompted for it when you invoke a command Both cases are illustra
9. Storage Mode Matrix Defines the storage mode of a Matrix entity Se lections are COMPRESSED and UNCOMPRESSED See also Compressed Uncompressed Column major and Row major Stream Entity continuous stream of data values that may be directly and randomly addressed You may best think of this type of entity as a low level Unix or DOS file Subquery The portion of a query in which the selection of data is based on the results of another query Subscript An additional modifier for an eBase entity name which allows great flexibility in data modeling Substitution Symbol variable name or number which is used as an argument to an eQL command The symbol is preceded by an ampersand amp Type Matrix Definesthe data type of a Matrix entity Selections are INT RSP RDP CSP and CDP Uncompressed Storage Mode Matrix The Matrix entity storage mode in which all matrix terms are on the database See also Compressed Storage Mode Working Directory Your current location within the database directory hierarchy is called the Working Directory WRITE Privilege Allows users to write data onto the eBase database XYPLOT Isa graphic display of the results of a relational query GLOSSARY eShell Users Manual INDEX amp character 11 1 character 1 11 character 1 14 1 15 2 4 4 2 7 2 7 5 character 1 16 character 2 2 character 1 13 A Abbreviating commands 1 7 Absolute directory 2 1 Activ
10. XYPLOT TIME T1 T3 FROM THISTORY which results in the following graph with the graphics elements anno tated Transient Response Ti S 7 FTITLE m 0 6 d H A n fy 2 LEGEND sini ENS REL E 027 1 1 p lay 1 02 nn Hil i 4 oeth Y v DRAWLINE 0 8 jos T SYMBOL 0 0 02 0 04 0 06 0 08 0 1 0 12 0 14 0 16 XTITLE Customizing the Axes There are several commands which allow you to control the x and y axes of your graphs which are described in this section Changing the Axis Range You may change the ranges of the graph by giving the largest and smallest values that you want displayed on either axis This is done with the commands XMIN XMAX YMIN TO value YMAX Note that you may place multiple selections in as single command such as GRAPHING RETRIEVED DATA 5 5 User s Manual 5 6 eShell o ET XMIN TO 0 0 XMAX TO 1000 0 YMIN TO 2 0 YMAX TO 4 5 Similar to the titling commands these ranges remain in effect until cleared with XMIN XMAX YMIN f YMAX CLEAR Remember that axis ranges remain in effect until you either redefine them or CLEAR them Logarithmic Scales In addition to specifying a data range you may also have one or both axes represented by a logarithmic scale with the com mands XLOG YLOG You m
11. FILE ENVIRONMENT COMMANDS 11 3 Users Manual eShell The file is positioned to the end of data upon completion of this opera tion If the file is enabled again subsequent data will be appended to the end of the file Only one Interface File may be used at a given time If another SET INTERFACE command is encountered the current open file will be closed and the new one opened Note that no format checking is done by eShell It is your responsibilit 8 y y y US to insure that the format statement specified is compatible with the output data items The interface file format for Matrix data is fixed If you need to export Matrix entities you can read them in a program that you write which uses a special Fortran utility which is part of the eBase applib Contact your eBase Administrator to obtain this routine The actual internal file format is documented in the Installation Guide and System Support Manual EXPORTING AND IMPORTING DATABASES You may move an eBase database from one computer to another as shown in Figure 11 1 Given an eBase database residing on host com puter A you may create an Export File in one of two formats described later in this section This file is then transferred using the network proto cols available at your facility to host computer B You then use eShell on this computer to load the resulting Import File into a new eBase database residing on computer B Figure 11 1 Moving a Database To a New Computer
12. HOST HOST COMPUTER COMPUTER A B eShell on A eShell on B NETWORK TRANSFER IMPORT FILE EXPORT FILE une Ne UN 11 4 FILE ENVIRONMENT COMMANDS eShell Users Manual The commands used for this purpose are BINARY EXPORT path TE file name and IMPORT file name path The optional path descriptor indicates that a recursive descent of all subdirectories from path and their contents will be EXPORTed In the case of IMPORT all of the directory structure previously EXPORTed will be restored treating the specified path as the Root Directory There are two basic types of file The first is BINARY which represents data using the IEEE 754 1985 Binary Floating Point Arithmetic Standard to represent the data contents of the eBase Export Files of this type require the minimum amount of disk space and thus require the shortest transfer time across your network The second type of file is the FORMAT TED file When you use this option the resulting file shows all eBase data items as clear text This option results in much larger Export Files The file name that you specify depends on the naming conventions of the two computers that are used for the transfer of the database Note that IMPORT automatically detects the file type when restoring the database When you use the BINARY file option it is possible that certain data may lose precision when moving from one type of comp
13. You may specify a different string for the System ps the User pu and the Local p1 preference files If you have the unusual case where all of these files have the same name you may use the option p followed by the prefname database Is the name of a database to be opened with read access This places you in the command mode Unless directed otherwise by eShell commands all subsequent output will be sent to the terminal de vice The optional prefname information is an advanced feature used for customizing eShell which is described in the Installation Guide and System Support Manual Online HELP INTRODUCTION eShell provides an online HELP feature to provide documentation of the features available in the program The command used is HELP command part list If HELP is specified without any additional parameters a listing of avail able command parts is given You may then obtain additional informa tion by picking from a menu If the command part list is provided then information relating to the named command parts is presented without menu interaction Additionally you may use the uaidoc utility to view this manual online using the Adobe Acrobat Reader 3 0 which is delivered with your software To do this you launch the Reader in a new window User s Manual eShell Accessing Databases The first command used selects an eBase database that you wish to open for access This is done with the command NEW
14. in engineering and physical science software applications A Matrix En tity is defined in the standard mathematical manner as an array of n Rows and m Columns 11 412 Alm 12 022 adm 1 4n2 Anm Each value in the Matrix is called a Term The subscripts i and j indi cate the row and column location of the term Matrices also have schema components These include the Orientation the Storage Mode the Nu meric types of their terms and their general topological Shape As with Relations the schema is defined when the Matrix is created A Matrix which is entered by columns has a Col umn major orientation and one which is entered Figure 1 5 MATRIX Entity UNCOMPRESSED MODE by rows has a Row major orientation The COLUMN1 1 0 3 1 0 0 0 0 0 0 Shape of a Matrix represents its general topol COLUMN ZSR Dun ogy such as square or rectangular The Numeric COLUMN 3 06 10 35 02600 type of a Matrix specifies the type of data defin COLUMN 4 3 0 0 0 0 1 5 2 3 4 0 ing its terms For example the terms can be real or complex Finally you may select from two COMPRESSED MODE possible Storage Modes for the Matrix The first COLUMN 1 gt 1 0 3 1 mode is Uncompressed in which case all of the COLUMN 2 usw 25 Matrix terms are stored on the database To im prove efficiency eBase uses an optional tech COLUMN3 gt 1 355 0 2 2 niq
15. p lt p if and only if a lt p 6 o p if and only if a p 6 The tolerance is specified with the command SET TOLERANCE TO value PERCENT where the value given corresponds to 6 If the optional keyword PER CENT is given then the tolerance is set to that percentage of a given p 6 value p 100 0 The default value for the tolerance is 1 0E 6 eShell provides an online HELP feature to provide documentation of the features available in the program The command used is HELP command part list If HELP is specified without any additional parameters a listing of avail able command parts is given The user may then obtain additional in formation by picking from a menu If the command part list is provided then information relating to the named command parts is presented without menu interaction UTLITIES eShell Users Manual ENVIRONMENT SETTINGS UTLITIES Because there are many environment variables that may be SET a special command is available to list their current values This command is SHOW variable class list If the optional variable class list is not given then all environ ment parameters will be shown Otherwise one or more vari able class terms may be selected FILES COLUMNS PAGE VERSION CONFIG OPEN DATABASES variable class list where FILES requests a summary of the active files COLUMNS a sum mary of current report formatting data for all attributes PAGE a
16. use These passwords allow READ WRITE and ADMINISTRATION privileges Path sequence of Directory names which indicates a location within the directory hierarchy Privilege The database access allowed by a user These are defined by the READ WRITE and ADMINISTRATION passwords See also Passwords Query An eQL command which retrieves data from one or more eBase Relational or Matrix entities READ Privilege Allows users to read data from the eBase database Relational Entity A table of data eBase tables have rows which are called Entries and columns which are called Attributes A particular data value at a given entry and attribute location is called a Field See also Entries Attributes and Fields Report File A file which captures all query and report output for which you wish to obtain hardcopy Root Directory When you OPEN an eShell database you will be placed in the root directory of that database Row major Method of storing a Matrix entity where the number of rows in the matrix is dynamic but the number of columns is fixed Schema A set of rules defining the data characteristics of a database entity B 3 User s Manual B 4 eShell Script File A text file that resides on the eShell host computer Unlike a Command File it may contain a sequence of many eQL commands Shape Matrix Defines the shape of a Matrix entity Selections are REC TANGULAR SQUARE SYMMETRIC DIAGONAL and IDENTITY
17. which has the standard form described in Chapter 4 can be used to update a specific range of selected data entries If it is not used then all of the entries in the entity are updated as speci fied Example 9 1 In Directory TUTOR copy the Relation QUAD4 to NEW_QUAD4 change the property identification number of all element to the value 1 and verify the change COPY GEOM QUAD4 TO NEW_QUAD4 1 Entity Copied UP NEW_QUAD4 SET PID 1 10 Entries Updated SELECT FROM NEW_QUAD4 4 Entries Selected The modification of more than one attribute is accomplished simply by listing all of the new values desired in the UPDATE command as illus trated in the next example Example 9 2 Copy the Relation PSHELL to NEW_PSHELL and change the material property identification number and the thick ness to 501 and 0 25 respectively Verify the results COPY MODEL PSHELL TO NEW_PSHELL 1 Entity Copied UPDATE PSHELL SET MID 501 T 0 25 3 Entries Updated LECT FROM PSHELL 2 50000E 01 2 50000E 01 2 50000E 01 3 Entries Selected It is also possible to update a set of entries simultaneously by using a WHERE part that contains the appropriate collection of conditions Example 9 3 Make a copy of Relation GRID called NEW GRID and translate the grid point having an X coordinate of 2 0 and a Y coordinate of 1 0 to the location having Y 2 0 eSh COPY GEOM GRID TO NEW GRID Entity Copied eSh g
18. 0 0 This results in the plot Transient Response JL as EE D l 0344 I A t LIT A ail tuU jJ lig AL dite Aon WW SHER PHA GRAPHING RETRIEVED DATA eShell Users Manual When Relational operations are performed between floating point values it is possible for the numeric representations to cause testing failure This is corrected by the use of a floating point TOLERANCE on the operations as described in Chapter 13 Table 5 1 reiterates the allowable logical and Relational operators that may be used in a search expression The next example illustrates the use of a logical combination of two Rela tional operations Example 5 7 Plot the displacement component T3 for all time steps greater than than 0 04 and less than 0 1 SET YTITLE TO Z Displacement Narrow Time Range XYPLOT TIME T3 FROM THISTORY WHERE TIME gt 0 04 AND lt 0 1 This results in the following plot Transient Response 0 8 je ee Z Displacement Narrow Time Range o 1 7 4 a m Parentheses may be used to group and clarify more complex expressions appearing in the search_condition Example 5 8 Plot the displacement component T3 for all time steps greater than 0 02 and less than 0 06 or whose time step is greater than is 0 12 SET YTIT
19. 1 2 Data modeling 1 2 Data values See Stream entities Dates on report pages 12 4 DEFINE eQL command 1 2 1 15 11 2 DELETE command line eQL command 1 14 DELETE eQL commands FREEFORM 10 4 MATRIX 10 3 RELATION 10 2 DESCRIBE eQL command 2 6 Difference of two relations 4 18 Dimensionality of entities 3 6 DIR eQL command 1 3 2 3 2 5 Directory chain 2 2 Directory hierarchy Absolute directory 2 1 Changing directories 2 2 Creating 2 2 Description 1 3 DIR using entity specification 2 5 DIR using path specification 2 3 Fully qualified entity name 2 1 Listing 2 3 Referencing in commands 2 1 Relative directory 2 1 Removing 2 3 Root directory 2 2 Working directory 2 2 Directory tree 13 1 Distinct attributes selecting 4 2 DISTINCT option in SELECT 4 2 E eBASE Description of 1 1 Directory hierarchy 1 3 Organization of 1 2 eBASE APPLIB 1 2 eBASE MATLIB 1 2 Editing eQLcommands 1 14 Index 2 eShell END eQL command 1 15 ENTER command line eOL command 1 14 Entity 1 2 Entity classes Description of 1 4 Dimensionality 3 6 Freeform 1 6 Matrix 1 5 Relational 1 5 Stream 1 6 Entity subscripts 1 4 Entries 1 5 Environment Showing current values 13 3 Environment files showing current file names 13 3 Environment variables 1 13 eQL command syntax Abbreviating 1 7 Active command 1 13 Case sensitivity 1 11 Description 1 7 Editing 1 14 Multiple line entry 1 13 Substitution variables 11 1 Symbol substitutions 1 15 eQL command
20. 13 User s Manual eShell This results in a single plot that includes nine curves one for each value of NITER The scaling of the plots encompasses the full range of values found in the data The final plot is shown below i VAI GRAPHING RETRIEVED DATA eShell Users Manual 6 INDEXING RELATIONAL ENTITIES THE INDEX CONCEPT CREATING THE INDEX When you perform queries on very large Relational entities they may require a significant amount of elapsed time To improve response time you may build one or more Indexes for a Relation The methods for doing this are described in this Chapter An index for a Relational entity serves the same purpose as an index in a book it allows faster access to the information that you wish to find Similarly eShell allows you to build one or more indexes for the attrib utes of a Relation so that the program may gain rapid access to the data If a Relation has no index then all queries must search through the data sequentially As a result indexes can dramatically increase the speed with which queries are performed You create an index for a Relation with the command CREATE UNIQUE INDEX ON rel name attr name list The rel name is the name of an existing Relation and attr name list specifies one or more attribute names for which the index will be created These attributes form the Key for each
21. Freeform and Stream Numeric Data Types SYMBOL KEYWORD DESCRIPTION INT Integer Terms RSP Real Single Precision Terms num type RDP Real Double Precision Terms CSP Complex Single Precision Terms CDP Complex Double Precision Terms MIXED Heterogeneous Terms User s Manual eShell CREATING STREAM ENTITIES New Stream entities may be also be created as long as they are schematic They are created with the command CREATE STREAM stream name _ LIKE old stream name where the stream name is the entity name Again the Stream has a single characteristic its Numeric Type num type also shown in Table 3 3 ADMINISTRATION privilege is required to create these entities and the LIKE clause may be specified to use the attributes of an existing entity CREATING SUBSCRIPTED ENTITIES 3 6 When you create a subscripted entity of any class the first creation deter mines the Dimensionality or number of subscripts that will be used for all subsequent subscripted versions of the entity that you create An error will occur if you attempt to specify an entity with the wrong Dimension ality in any eQL command Clean up your TUTOR Directory to restore your TESTEB database to its initial state CREATING eBase ENTITIES eShell Users Manual 4 RETRIEVING DATA FROM RELATIONS THE SELECT COMMAND The most powerful use of the eQL lang
22. MAX Find the algebraically largest value of the expression COUNT Counts the number of entries satisfying the given conditions RETRIEVING DATA FROM RELATIONS 4 15 User s Manual 4 16 eShell with group functions but these functions may not be used in other arith metic expressions Example 4 24 Find the maximum Normal X stress and minimum Nor mal Y stress for Subcase 1 eSh SELECT MAX SIGX MIN SIGY 2 FROM Q4STR 1 SIGX MIN SIGY 3 00000E 06 1 00000E 06 1 Entry Selected When using group functions it is not allowed to also select individual attributes such as eSh SELECT GID AVG SQRT X 2 Y 2 Z 2 FROM GRID unless the individual attributes are later specified in a GROUP part of the query This is because attributes refer to fields within each entry whereas the group operation refers to all entries Example 4 25 Find all grid points which have the greatest X coordinate eSh SELECT GID FROM GRID 2 WHERE X SELECT MAX X FROM GRID 2 Entries Selected There is one case in which single attribute names may appear in a SE LECT command along with group operators This is allowed when a GROUP part is included as part of the selection criteria as shown in the next example It is this feature that differentiates the grouping and order ing operations Also note that in this case the subquery returns a single value Therefore the strict equality is specified witho
23. PURPOSE LOGICAL TRUTH TABLES AND Logical conjunction AND T F OR Logical disjunction T T F NOT Logical Negation F F F Equality lt gt Inequality Less than gt Greater than OR lt Less than or equal T gt Greater than or equal Example 4 7 Select the grid point identification number GID for all grid points with X coordinates greater than 2 0 and Y co ordinates equal to 0 0 eSh SELECT GID FROM GRID WHERE X gt 2 0 AND Y 0 0 2 Entries Selected Parentheses may be used to group and clarify more complex expressions appearing in the search condition Example 4 8 Select the grid point identification number GID and X co ordinate for all grid points with X coordinates greater than 2 0 and Y coordinates equal to 0 0 or whose GID is 1 eSh SELECT GID X FROM GRID 2 WHERE X gt 2 0 AND Y OR GID 1 0 00000E 00 3 00000E 00 10 4 00000 00 3 Entries Selected RETRIEVING DATA FROM RELATIONS 4 5 User s Manual eShell SELECTING FROM A SET COMPARING TO A SET A special operator IN is available to allow a selection of data to be based upon a set of specific values A Set is a finite group of values with consis tent data types You may also select from values not in the set by using the optional keyword NOT The general form of the WHERE clause to do this is WHERE attribute name NOT IN set definition where the set definition is one or more
24. RECORD DATA LENGTH 1 107 25 10 20 10 2 2 0 4 0 40 0 20 3 3 0 6 0 90 0 30 4 4 0 8 0 160 0 40 5 5 0 10 0 250 0 50 O MODEL STRM is a Stream Entity of type integer INT containing 1000 Data Values which are equal to the Position within the Entity O The PLOT directory includes a number of Relations that contain larger amounts of data suitable for demonstrating the XYPLOT com mands presented in Chapter 5 You may use the DIR and DESCRIBE commands to get information about these INTRODUCTION User s Manual eShell Figure 1 8 Sample eBase Database TESTEB RELATION GEOM QUAD4 D PID G1 G2 G3 G4 1 kj 8 9 N e BC N rR 2 1 2 Jw IN o 10 RELATION MODEL PSHELL PID MID T 1 101 2 201 0 5 3 301 0 3 RELATION RESULT Q4STR 2 EID SIGX SIGY TAUXY 0 7 0 0 3 0 3 0 6 1 0 7 6 0 3 0 0 1 0 4 1 7 2 3 3 5 077 4 2 0 6 1 0 6 5 0 4 RELATION RESULT BIGREL ATT1 ATT2 ATT3 See Text MATRIX MODEL KGG Orientation COLUMN MAJOR Mode COMPRESSED Numeric Type RDP
25. RELATIONS eShell GROUP OPERATORS Users Manual Example 4 22 Find the GID and X coordinate of each grid point that appears as the first grid point in a QUAD4 element which has a thickness of 0 1 eSh SELECT GID X FROM GRID 2 WHERE GID IN SELECT Gl FROM QUAD4 WHERE PID IN SELECT PID FROM MODEL PSHELL WHERE T 20 1 0 00000E 00 2 00000E 00 2 Entries Selected In addition to the arithmetic and logical operators that have been de scribed eQL also supports certain group operators These operators are so designated because they are performed on one or more attributes across a group of entries from a Relation These group functions are shown in Table 4 3 The use of the group functions is like that of normal arithmetic functions namely the argument must be enclosed in parentheses Example 4 23 Find the average X coordinate for all grid points having a Y coordinate of 1 0 eSh SELECT AVG X FROM GRID WHERE Y 2 00000 00 1 Entry Selected Naturally the WHERE part restricts the set of data for which the func tion AVG in this case is applied Multiple attributes may be computed Table 4 3 Group Operators OPERATOR DESCRIPTION Computes the average value of the specified attribute expression AVG aes T for all entries satisfying the selection criteria SUM Computes the arithmetic sum of the expression MIN Finds the algebraically smallest value of the expression
26. TEMP OPEN database name phys name READ params WITH WRITE ADMIN The database name specifies the name of an existing eBase database or a database that you are creating during your current session The op tional phys name overrides the name of the database as viewed by the operating system On operating systems which use the file name to iden tify the location of the files this also gives you the ability to override the configuration parameters which would otherwise control the location of the database files For nonexisting databases you may specify a status of NEW or TEMPorary when you open it Temporary databases do not have any password protection since they are deleted at the end of your eShell session For a new database you will be prompted for an ADMINISTRA TION password This password will also be used for READ and WRITE access You may change any of the passwords with the SET PASSWORDS command described later in this Chapter For existing databases you are prompted for the appropriate access password for the database Some host computers require additional info ration which is specified as optional params see the Installation Guide and System Support Manual for a discussion of these The initial part of the eShell session is shown in the following example Example 1 1 Execute the eShell program for an eBase named MY EB eshell eShell Version 20 0 dd mmm yy 14 22 Copyright c 1992 1997 Universal Analyti
27. WRITE and ADMINISTRATION privi leges Because the principal intent of eBase is the development of soft ware applications it has not been designed to have the comprehensive security protections often found in the financially oriented products The READ privilege allows a user to read all of the Entities on the data base and to perform any operation which does not create modify or delete information from it The WRITE privilege extends access to allow Entities to be modified and deleted from the database Finally the AD MINISTRATION privilege allows all possible database operations The command which allows you to change your eBase passwords during an eShell session is SET PASSWORDS ON database name password list where password listisalist of one or more password terms which define new values for any or all of the passwords These terms have the form READ WRITE password ADMIN password term READ CLEAR WRITE ADMIN If you do not specify a database name then the passwords are changed for the current database You may only change the passwords if you have the ADMINISTRATION privilege level for the database The CLEAR option may be used to remove any level of password protection INTRODUCTION eShell DATABASE INTEGRITY Users Manual Because the primary design goals of eBase are flexibility and perform ance in scientific software application it does not provide extensive data integrity features which result in the
28. few restrictions as possible While there are no categorically reserved words in the language there are some which cannot be used in particular circumstances Rather than enumerat ing these it is best if you do not use the words shown below for names that you use in your database BINARY INTER or INTERSECTION DIFF or DIFFERENCE MAT or MATRIX DISTINCT ORDER FORMATTED SEL or SELECT FREE or FREEFORM STR or STREAM FROM UNION GROUP WHERE User s Manual eShell Size Limitations USING THE TUTORIAL 1 18 There are no practicable limitations on the size or composition of an eBase database All limitations are imposed by the architecture of the host computer The only quantifiable limitation is that any Command Part which requires an integer value such as as Matrix row or column number a Freeform record number or a Stream Data Value cannot ex ceed the largest representable integer on the host computer The smallest value for eShell computers is greater than two billion i e 2x10 This manual provides all of the information necessary to use eShell and the eQL language Command usage is liberally illustrated by examples taken from a small sample database shown in Figure 1 8 This database has been delivered with eShell and is intended to be used as a tutorial to teach you the fundamentals of eShell Contact your Administrator if you wish to have your own copy of the tutorial database called TESTEB and a copy of the Command Fi
29. from Relation QUAD4 eSh CD GEOM eSh SELECT EID PID G1 G2 G3 G4 FROM QUAD4 4 Entries Sel Note that there is a special shorthand that can be used when selecting all the attributes SELECT FROM GRID Any subset of attributes may be selected and the resulting output pre sents the attributes in the order in which they are named on the SELECT command Example 4 2 Select only the G1 and G4 attributes from Relation QUAD4 first selecting G4 eSh SELECT G4 G1 FROM QUAD4 4 Entries Selected The SELECT command also allows you to only select entries from the Relation which have distinct values for all SELECTed attributes The command is modified slightly as SELECT DISTINCT attrib list FROM rel name RETRIEVING DATA FROM RELATIONS eShell Users Manual Example 4 3 Select the distinct property identification numbers from Relation QUAD4 eSh SELECT DISTINCT PID FROM QUAD4 2 Entries Selected THE OUTPUT FORMAT Examples 4 1 and 4 2 illustrate the type of output that appears when a query is performed A description of the general format of this output and the manner in which you may modify it are given in Chapter 12 ATTRIBUTES WHICH ARE ARRAYS If an attribute of a Relation is an array i e its length is greater than one then all of the elements of the array are displayed when queried Although the sample database does not contain a Relation with such attributes consider the follo
30. high overhead of many non scien tific database products It does however provide several levels of data integrity This is done through configuration parameters which force fre quent physical data transfers WORKING WITH MULTIPLE DATABASES eShell allows you to use any number of eBase databases that you have previously created or obtained from an external source As you will see in subsequent Chapters of this manual you may define multiple data bases and address the entire directory structure of each MOVING DATABASES BETWEEN COMPUTERS eShell LIMITATIONS eShell allows you to move eBase databases from one computer to an other Options are available to export a database in either character for mat or in binary format using the IEEE 754 1985 Binary Floating Point Arithmetic Standard Such database files may then be transferred to other computers and then imported into eShell This may only be done success fully for completely schematic data which includes all Relational Entities all Matrix Entities Schematic Freeform and Schematic Stream Entities Details of this procedure are given in Chapter 11 of this manual Many databases have severe size limitations and their query languages long lists of Reserved Words those which you cannot use for other pur poses eShell and eBase have reduced such problematic limits dramati cally as described in the following sections Reserved Words INTRODUCTION eQL has been designed to have as
31. host computer that will contain an archive created from user input commands eQL COMMAND SUMMARY eShell Users Manual ON ARCHIVE OEF Enables and disables the archive file SET REPORT TO file name Defines a file on the host computer that will contain reports created from output displays ON REPORT OFF Enables or disables the report file SET INTERFACE TO file name Defines a file on the host computer that will contain output displays which are written in a user specified format for subsequent processing by other programs INTERFACE Enables or disables the interface file INTERFACE FORMAT format specifier Defines a Fortran format to be used in writing to the interface file BINARY EXPORT path FORMATTED file name Creates an Export File used to move an eBase from one computer to another IMPORT file name path Restores a previously EXPORTed eBase Chapter 12 Report Generation eQL COMMAND SUMMARY This Chapter presents the methods available for generating customized reports suitable for inclusion in design reports SET COLUMN attribute name column options Allows the user to specify titling and format options for each column of a report column option heading info format info User s Manual A 12 eShell justification TEMP CLEAR Defines the available column options heading info LABEL
32. more indexes the results are modified slightly Example 2 11 Request a description of Relation 045 and suppose that two indexes have been created for it one on attribute EID and one on the combined attributes EID and CASE eSh DESCRIBE RESULT 04S Relation TESTEB RESULT Q4S Schema is Attribute Type Len INT INT GX RSP Bs GY RSP TAUXY RSP Current Contents 8 Entries 2 Indexes Exist on EID 2 on EID and CASE A complete discussion of indexing is found in Chapter 6 of this manual DIRECTORIES AND ENTITIES 2 7 User s Manual eShell RELEASING A SUBSCRIPTED VERSION As shown in earlier sections of this Chapter you may Release one of the subscripted versions of a subscripted entity This is done with the com mand RELEASE ent name The significance of a Released Version is that all eQL commands can now use the Basic Name of the entity without reference to a subscript Natu rally if you have not Released a version such commands will fail The Release a different version of the entity you simply use the RELEASE command and specify the new subscript If you want to remove a re leased version without assigning a new one then you use the command UNRELEASE ent name MANIPULATING ENTITIES 2 8 There are several operations that you may perform on entities or groups of entities that may simplify data management The first allows one entity to be copied to another thereby replicating
33. of the SELECT command SELECT attrib names FROM rel name WHERE search condition where a search conditionis logical expression of arbitrary complexity that involves any or all of the attributes in the Relation The terms in a 1ogical expression are themselves Relational ex pressions All of the rules for evaluating logical and Relational expres sions follow the standard rules of Fortran Example 4 6 Select those grid points from Relation GRID that have X coordinates greater that 3 0 eSh SET TOLERANCE TO 0 0 eSh SELECT FROM GRID WHERE X 3 0 4 00000 00 1 00000 00 0 00000E 00 4 00000E 00 0 00000E 00 0 00000E 00 2 Entries Selected Note that the SET TOLERANCE command is used to override your con figuration default value for this and subsequent examples Note that when Relational operations are performed between floating point values it is possible for the numeric representations to cause testing failure This is corrected by the use of a floating point TOLERANCE on the operations as described in Chapter 13 Table 4 1 lists the allowable logical and Relational operators that may be used in a search_expression The next example illustrates the use of a logical combination of two Relational terms RETRIEVING DATA FROM RELATIONS eShell Users Manual Table 4 1 Logical and Relational Operators OPERATOR
34. qualify or constrain the record selection with a Freeform WHERE part of the form RECORD WHERE part WHERE d RECORDS IN record list where the record list is a list of one or more integer record num bers When selecting a single record the alternate form which requires only the single num may be used Example 7 5 Query Freeform TESTFREE selecting Data Values 1 5 and 10 from Records 2 and 5 eSh FREE SELECT 1 5 10 FROM TESTFREE WHERE RECORDS IN 2 5 Real Single Precision 5 Records 50 Data Values in Longest Record 2 20 Data Values 2 00000 10 0000 20 000 Record 5 50 Data Values 5 00000 25 0000 50 0000 Note that the total length of the Record is always given See Chapter 12 for a description of the ways in which you can control the format of the Freeform query RETRIEVING DATA FROM NON RELATIONAL ENTITIES eShell Users Manual STREAM ENTITIES This section describes the command that you may use to retrieve data from Stream entities This command is very similar to the one for query ing Freeform entities As with Freeform entities data can also be selected from Stream entities if they are Schematic The general form of the Stream query command is STREAM SELECT select list FROM stream name where the select list is the same as that described for the FREEFORM SELECT and stream name is the name of an existing Stream entity Example 7 6 Query the Stream entity STRM and print t
35. row in a Relational entity eQL Is the eBase Query Language based on the SQL standard for data base languages Export File An external host computer file which contains a binary or formatted version of one or more entities contained in a specified directory tree which can then be moved to a different host computer See also Import File Field Field is a single data item in a Relational entity It is found at a single row and column position in the table Freeform Entity Area form of internal data representation that can some times be used to improve the performance of software applications They are collections of data with only a local and transient purpose You may think of Freeform entities as Fortran random files which have variable length records Because of its portability limitations the use of the non schematic form of this entity class is discouraged for other than temporary data Import File An external host computer file which contains a binary or formatted version of one or more entities that were contained in a specified directory tree that have been moved from a different host computer See also Export File Index Anindex fora Relational entity serves the same purpose as an index in a book it allows faster access to the information that you wish to find eShell allows you to build one or more indexes for the attributes of a relation so that the program may gain rapid access to the data Integrity The pr
36. subscripts Displacement 6 Subscript not integer File Naming Conventions There are a number of host computer files that may be used during your eShell session These include the actual database name eQL Command Files Archive Files Report Files and Interface Files File names which do not satisfy the Basic Naming Rules described above must be enclosed in tics the actual format of the name used depends on your eShell host computer and is described in the System Interface Manual 1 10 INTRODUCTION eShell Users Manual USING THE eShell PROGRAM This section provides you with instructions for using eShell selecting eBase databases and entering commands Generally eShell is Case in sensitive upper and lower case letters may be used interchangeably When names or command parameters contain embedded blanks or other special characters they must be enclosed in single quotation marks sometimes called tics as in HI THERE Also note that when enclosed in tics letters are case sensitive Getting Started Usually eShell is installed on the host computer as a system procedure You must check with your computer system manager to determine if your system has been installed differently To execute the program from the command line you enter eshell ps prefname pu prefname pl prefname database where prefname Specifies the substitution string used to generate Preference File names
37. the ADDCURVES command they must GRAPHING RETRIEVED DATA 5 11 User s Manual 5 12 eShell appear in the order indicated The specified curve or curves will be added to the graph in the active plot window If the domains of the x attrib and y attrib list are different from those of the curves already plotted then all data are rescaled using the union of the data domains Remember that the total number of curves on a plot may not exceed nine Thus the sum of the original number of plots created by the XYPLOT command plus those specified by the y attrib list of the ADDCURVES command cannot exceed this value Example 5 11 From directory plot create a plot of VELO versus DAMPV from the relation ROOTS where MODE 5 and NITER 1 After this is com pleted successively add new curves for values of NITER equal to 3 5 and 8 XYPLOT VELO DAMPV FROM ROOTS WHERE NITER 1 AND MODE 5 ADDCURVES VELO DAMPV FROM ROOTS WHERE NITER 3 AND MODE 5 ADDCURVES VELO DAMPV FROM ROOTS WHERE NITER 5 AND MODE 5 ADDCURVES VELO DAMPV FROM ROOTS WHERE NITER 8 AND MODE 5 Which results in the sequence of plots shown below 0 025 002 D MPV DAMPV e u DAMPV 2004 m 20 035 0 045 GRAPHING RETRIEVED DATA eSh
38. values separated by com mas for the attribute name which are to be selected from the Rela tion Example 4 9 Select all grid points with X coordinates of 3 0 or 4 0 using a set definition eSh SELECT GID X Y Z FROM GRID WHERE X IN 3 0 4 0 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 00000 00 4 Entries Selected It is also possible to compare an attribute to a set of values using the form WHERE attribute name rel operator ALL SOME subquery ANY Any of the rel operators shown in Table 4 1 may be used in this expression This comparison is used when you wish to quantify the members of a subquery which is described later in this Chapter USING ARITHMETIC EXPRESSIONS 4 6 The last two sections have illustrated how logical and Relational expres sions can be used to qualify the data to be selected from a Relation eQL commands can also contain arithmetic expressions that combine at tribute names constants and functions Such expressions can be used as selections When this is done the selection is called a Virtual Attribute because it only exists as the result of the query of the rules for arithmetic expression evaluation also follow the standard rules of For tran RETRIEVING DATA FROM RELATIONS eShell Users Manual Table 4 2 Arithmetic Functions
39. with a WHERE part in the usual manner The WHERE part is optional and if it is not specified then all data entries are deleted from the Relation Example 10 1 In Directory TUTOR make a copy of Relation GRID and delete entries which have Y coordinates equal to 0 0 and verify the results CD TUTOR COPY GEOM GRID TO DEL GRID 1 Entity Copied DELETE FROM DEL GRID WHERE Y 0 0 Enter YES to delete 5 Entries leaving 5 Entries YES 5 Entries Deleted from TESTEB TUTOR DEL GRID SEL FROM DEL GRID 5 Entries Selected It is equally permissable for subqueries to be used in the WHERE part as shown in the next example Example 10 2 Make a copy of Relation PSHELL and remove the entry which has the same property identification number PID as element identification number 2 in Relation QUAD4 and verify the result COPY MODEL PSHELL TO DEL PSHELL 1 Entity Copied DEL FROM DEL PSHELL WHERE PID SELECT PID FROM GEOM QUAD4 WHERE EID 2 Enter YES to delete 1 Entry leaving 2 Entries YES 1 Entry Deleted from TESTEB TUTOR DEL PSHELL SELECT FROM DEL PSHELL 1 00000E 01 3 00000E 01 2 Entries Selected Note that Relation GEOM QUAD4 in the Subquery is fully qualified because the Working Directory is TUTOR 10 2 REMOVING DATA FROM eBase eShell Users Manual REMOVING COLUMNS OR ROWS FROM MATRICES It is also possible to remove selected columns or rows from Matrix enti ties depending on th
40. you DELETE one or more Records from a Freeform entity all 3 Records are renumbered Therefore you cannot reference Records by their original number EB database to Clean up your TUTOR Directory to restore your TES v its initial state 10 4 REMOVING DATA FROM eBase eShell Users Manual 11 FILE ENVIRONMENT COMMANDS THE SCRIPT FILE eShell provides a class of commands that can modify the file environ ment under which the program performs certain operations These com mands allow the user to modify the source of eQL commands to define a file upon which eQL commands may be written for archival purposes or to create text files that may be used directly by other programs This section describes these features and the manner in which they are used A Script File is a text file that resides on the eShell host computer It may contain a sequence of many eQL commands When using eShell the command START file name param list requests that eShell begin reading and executing commands from the script file rather than from the terminal The name which must be enclosed in tics if it does not follow the Basic Naming Conventions de scribed in Chapter 1 may be any valid file name on the eShell host computer eQL Script Files may include parameters that you may change when you START them by specifying a param 1ist This is done by using a substi tution variable in the command The fo
41. 5 0 eSh UPDATE MATRIX NEW KGG 2 SET VALUES AT TERM 1 TO 5 0 WHERE COLUMN 5 ERR Cannot Update Matrix NEW KGG at Column Row 5 Row Column 1 The WRITE privilege is also required to UPDATE a Matrix entity UPDATING FREEFORM ENTITIES Freeform entities may be updated in a limited manner with the com mand UPDATE FREEFORM free name SET position TO value list WHERE RECORD rec id where the ree name is the name of an existing Freeform entity The value list is a list of one or more values that will replace all of the Data Items in rec id beginning with position Finally rec idis the Record that you wish to update 9 4 UPDATING ENTITY DATA eShell is User s Manual Example 9 7 Copy Freeform entity TESTFREE to UP FREE and change the second and third Data Values in the first Record to the values 22 2 and 33 3 respectively and verify the change eSh gt COPY MODEL TESTFREE TO UP_FREE 1 Entity Copied eSh UP FREE UP FREE SET 2 TO 22 2 33 3 WHERE RECORD Record Updated in TESTEB TUTOR UP FREE eSh FREE SELECT 1 2 3 4 5 FROM UP FREE WHERE RECORD 1 Single Precision 5 Records 50 Data Values in Longest Record 1 10 Data Values 1 00000 22 2000 33 3000 4 00000 5 00000 The entity must be a Schematic Freeform and the value list Nu meric Types must be the same as that defined for the entity The UPDATE FREEFORM command requires the WRITE privilege You may not
42. A more complete discussion of these descriptors appears in Chapter 3 eSh DESCRIBE TESTFREE Freeform TESTEB MODEL TESTFREE 5 Records Longest Record is 50 Numeric Type INT eSh DESCRIBE STRM Stream TESTEB MODEL STRM 1000 Data Values Numeric Type RSP 2 6 DIRECTORIES AND ENTITIES eShell Users Manual For Freeform entities the information reported includes the number of records in the entity and the length of the longest record Similarly for Stream entities the Numeric Type and number of Data Values is re ported As discussed in Chapter 1 no operations other than DESCRIBE or PURGE may be performed on Freeform or Stream entities unless they are Schematic To DESCRIBE subscripted entities there are two options as shown in the next two examples Example 2 10 Request a description for subscripted entity O4STR 2 eSh DESCRIBE RESULT Q4STR 2 Relation TESTEB RESULT Q4STR 2 Schema is Attribute Type Len eie INT SIGX RSP es EGY RSP TAUXY RSP Current Contents 4 Entries In this example an explicit subscripted version was included as part of the ent name given If an entity has subscripted versions and you do not specify a version then you will obtain a description of the Released version of the entity If there is no Released Version then you will receive a message to that effect RELATIONS WITH INDEXED ATTRIBUTES When you DESCRIBE a Relation for which you have created one or
43. Advanced CAE Applications for Professionals Software that works for eShell User s Manual Version 20 1 UNIVERSAL ANALYTICS INC Publication EB 001 1992 1999 UNIVERSAL ANALYTICS INC Torrance California USA All Rights Reserved First Printing November 1995 Second Printing December 1997 Third Printing February 1999 Restricted Rights Legend The use duplication or disclosure of the information contained in this document is subject to the restrictions set forth in your Software License Agreement with Universal Analytics Inc Use duplica tion or disclosure by the Government of the United States is subject to the restrictions set forth in Subdivision b 3 ii of the Rights in Technical Data and Computer Software clause 48 CFR 252 227 7013 The information contained herein is subject to change without notice Universal Analytics Inc does not warrant that this document is free of errors or defects and assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein UNIVERSAL ANALYTICS INC 3625 Del Amo Blvd Suite 370 Torrance CA 90503 Tel 310 214 2922 FAX 310 214 3420 eShell Users Manual TABLE OF CONTENTS 1 INTRODUCTION THE eBase SOFTWARE SUITE 1 1 DATA MODELING 57 Peia ue oe EE RID POR TO YER as E dos Foo ES Pad emos 1 2 eBase ORGANIZA
44. Clean up your TUTOR Directory to restore your TES v its initial state UPDATING ENTITY DATA 9 7 User s Manual This page is intentionally blank eShell UPDATING ENTITY DATA eShell Users Manual 10 REMOVING DATA FROM eBase REMOVING AN ENTITY This Chapter describes the eQL commands that are used to remove enti ties and their data from the eBase database Complete entities including both their schema and contents may be purged Alternately all or se lected data entries may be deleted without removing the entity itself Any database entity may be removed from eBase with the command RELATION MATRIX FREEFORM STREAM PURGE entity name ALLVER where the entity name must refer to an existing entity of the selected class This command removes the Data Component of the entity and then removes the entity Name and Schema from the database The ALLVER option allows you to PURGE all Subscripted versions of the entity Because this is a potentially dangerous command you are asked to con firm the PURGE activity This is true for all of the commands described in this Chapter REMOVING DATA FROM eBase 10 1 User s Manual eShell REMOVING ENTRIES FROM RELATIONS eQL allows you to selectively remove entries from eBase Relations This is done with the command DELETE FROM RELATION rel name WHERE part where rel name is the name of an existing Relation The entries to be deleted can be selected
45. Column major Orientation and the COMPRESSED Storage Mode Define the terms of the new column to be KGG 2 7 25 0 KGG 5 7 30 0and KGG 6 7 40 0 Verify the result eSh COPY MODEL KGG TO INS KGG 1 Entity Copied eSh INSERT INTO MATRIX INS KGG 2 VALUES AT 2 25 0 3 VALUES AT 5 30 0 40 0 Column Added to TESTEB TUTOR INS KGG eSh MATRIX SELECT FULL FROM INS KGG 2 WHERE COLUMNS IN 7 Warning Matrix Shape may no longer be correct Column Major Compressed Real Double Precision Symmetric 7 Columns Density 52 0 0 0000 25 0000 0 0000 0 0000 30 0000 40 0000 The WRITE privilege is required to INSERT new data into Matrix enti ties INSERTING DATA INTO ENTITIES 8 3 User s Manual eShell When you INSERT into a Matrix entity the topological Shape may be changed You must use the SET MATRIX SHAPE command to make the Shape consistant with the data in the entity This is only important if the Matrices will be used with eBase matlib ADDING NEW RECORDS TO FREEFORM ENTITIES You may also insert a new Record into a Schematic Freeform entity with the command INSERT INTO FREEFORM free name VALUES value list The value list is a list of Data Values whose Numeric Types are conformable to those defined in the entity schema Example 8 5 In Directory TUTOR make a copy of Freeform entity TESTFREE named INS FREE add a sixth Record to it and verify the result
46. Data Values 1001 1002 1003 The WRITE privilege is also required to INSERT new data into Stream entities Clean up your TUTOR Directory to restore your TESTEB database to v its initial state INSERTING DATA INTO ENTITIES 8 5 User s Manual This page is intentionally blank eShell INSERTING DATA INTO ENTITIES eShell Users Manual 9 UPDATING ENTITY DATA In this Chapter commands which allow data in Relational Matrix Free form and Stream entities to be updated are described Also the com mand for altering the schema of an existing Relation is given UPDATING RELATIONAL ENTITIES It is possible for you to update any fields in a selected Relational entries with the command UPDATE RELATION rel name SET value list WHERE part The value listisalistof value terms separated by commas which are used to define values for one or more attributes in the entity There are two basic forms of this list UPDATE REL rel name att name value SET value list value term gt WHERE part att name expression where the att name is an attribute name in the selected Relation rel name The attribute can be assigned a value directly or it may be computed by an arithmetic expression The expression may contain any of the functions described in Chapter 4 and it may use any of the attributes contained in rel name UPDATING ENTITY DATA 9 1 User s Manual eShell The optional WHERE part
47. EMENTS Examples 5 1 and 5 2 illustrate the type of output that appears when a query is performed The XY Plots consist of certain Graph Elements which you may control with various eShell commands The available families of commands are described in the following sections Symbols and Lines Titling When you create a graph each data point is indicated by a symbol and the symbols are connected by lines You may manipulate these options with the commands SET SYMBOL TO One E SET DRAWLINE TO ON There are three different titling options for a graph These are the graph frame title the x axis title and the y axis title A legend is automatically placed on the plot that associates attribute names with their plot symbols The titles are set using the commands SET FTITLE TO text XTITLE ET SET YTITLE TO text In each command text is any character text that you wish to use for titling information Once you have set the titles they remain until you explicitly clear them using the commands GRAPHING RETRIEVED DATA eShell YTITLE P d E M he 4 1 7 Fi Users Manual FTITLE CLEAR XTITLE YTITLE Remember that the titles that you set remain in effect until you either redefine them or CLEAR them Example 5 3 Repeat example 5 2 adding titles to the graph eSh SET FTITLE TO Transient Response eSh SET XTITILE TO Time eSh SET YTITLE TO X Z Displacement eSh
48. Freeform entities 3 5 To create Matrix entities 3 4 To create Relations 3 2 To create Stream entities 3 6 Updating Freeform entities 9 5 Updating Stream entities 9 5 Projection 8 1 Protection 1 16 PURGE eQL command 1 10 10 1 PURGE INDEX eQL command 6 6 Q Query See also SELECT command Definition 4 1 R READ privilege Description 1 16 Records of Freeform entity 1 6 Relation Algebraic operations 4 18 Updating 9 2 Relational attributes Selecting all 4 2 Selecting in any order 4 2 Relational entities 1 5 Altering the schema 9 6 Attributes 1 5 Attributes of 3 1 Creating 3 1 DIFFERENCE 4 19 Directory entry 2 4 Entries 1 5 Fields 1 5 Index 5 Users Manual See also Indexing Inserting entries 8 2 INTERSECTION 4 18 Joining 4 8 Projection 8 1 Removing data from 10 2 See also Report generation UNION 4 18 Updating 9 1 Relative directory 2 1 RELEASE eQL command 2 8 Released version Changing 2 8 Directory 2 4 Removing 2 8 Selecting 2 8 Removing data from eBASE Columns or rows of a matrix 10 3 Complete entities 10 1 Entries from a RELATION 10 2 Removing directories 2 3 RENAME eQL command 2 8 REPLOT eOL command 5 2 Reportfile 11 3 Report generation Column labels 12 1 Formatting commands 12 1 Page control commands 12 5 Pagetitling 12 4 Reserved words 1 17 Restrictions On Matrix UPDATE operation 9 4 RMDIR eQL command 2 3 Root directory 2 2 Row major orientation 1 5 RUN command line eQL command 1 14
49. L PSHELL WHERE 2 PID SELECT PID FROM QUAD4 WHERE EID 4 5 00000E 01 1 Entry Selected RETRIEVING DATA FROM RELATIONS 4 13 User s Manual 4 14 eShell The subquery in the last example returned a single value which was used as the selection criteria Subqueries may also return a set of values that may be used to determine the selection Example 4 20 Find the shear stress TAUXY for Subcase 1 Q4STR 1 for all elements whose TAUXY is greater than all shear stresses in Subcase 2 OASTR 2 Select both the element EIDandthe TAUXY value eSh SELECT EID TAUXY FROM RESULT Q4STR 1 WHERE 2 TAUXY gt ALL SELECT TAUXY FROM RESULT Q4STR 2 4 00000 04 4 00000 04 5 00000E 04 3 Entries Selected The result of the subquery is a list of all TAUXY from the Relation Q4STR 2 Since it is desired to find the TAUXY which is greater than all of these values the quantifier ALL must be used More than one subquery may be used to perform the selection as shown next Example 4 21 Find the QUAD4 elements having a thickness of 0 5 and whose Normal X stress SIGX for Subcase 1 OASTR 1 is greater than 2 0E 6 SELECT EID FROM QUAD4 WHERE PID IN SELECT PID FROM MODEL PSHELL WHERE T 0 5 AND EID IN SELECT EID FROM RESULT Q4STR 1 WHERE SIGX gt 2 0E 6 1 Entry Selected Additionally subqueries may be nested to create complex selection crite ria RETRIEVING DATA FROM
50. LE TO Z Displacement Two Time Ranges XYPLOT TIME T3 FROM THISTORY WHERE TIME gt 0 02 AND TIME lt 0 06 OR TIME 0 12 which results in GRAPHING RETRIEVED DATA 5 9 User s Manual eShell Transient Response 0 8 Z Displacement Two Time Ranges i 0 02 0 04 0 06 0 08 0 1 0 12 0 14 0 16 SELECTING FROM A SET 5 10 A special operator IN is available to allow selection of data based upon a set of specific values A Set is a finite group of values with consistent data types You may also select from values not in the set by using the optional keyword NOT The general form of the WHERE clause to do this is WHERE attribute name NOT IN set definition where the set definition is one or more values separated by com mas for the attribute name which are to be selected from the Rela tion Example 5 9 Plot the X coordinates versus the grid point ID from the Relation GEOM GRID where the GID has one of the val ues1 2 8 9 or 10 CLEAR XTITLE CLEAR YTITLE CLEAR FTITLE CD GEOM XYPLOT GID X FROM GRID WHERE GID IN 1 2 8 9 10 which results in 4 x 3 5 GRAPHING RETRIEVED DATA eShell Users Manual USING ARITHMETIC EXPRESSIONS As you have seen in Chapter 4 eQL commands can contain arithmetic expressions that combine attribute names c
51. NDEX ent n nd ou fa eel Oe PUE nd A Oe ud dope 6 6 TABLE OF CONTENTS iii User s Manual eShell 7 RETRIEVING DATA FROM NON RELATIONAL ENTITIES MATRIXENTITIES Edo EUR eI de Ew duum ee eH EO E 7 1 The MATRIX Select Command 7 1 Qualifying the Columns or Rows 7 4 FREEFORM ENTITIES 22s aks sg Oe DAE C RUE qub XE eA ee ard d 7 5 The FREEFORM Select Command 7 5 Qualifying the Records 7 6 STREAM ENTITIES 3 0 eg veux pepe mI Re a Gil od Dea 7 7 8 INSERTING DATA INTO ENTITIES ADDING NEW ENTRIES TO RELATIONS 8 1 ADDING NEW COLUMNS OR ROWS 5 8 3 ADDING NEW RECORDS 5 8 4 ADDING DATA VALUES TOSTREAMENTITIES e 8 5 9 UPDATING ENTITY DATA UPDATING RELATIONALENTITIES 9 1 UPDATING MATRIX ENTITIES 9 3 RESTRICTIONS ON MATRIX UPDATING 9 4 UPDATING 5 9 4 UPDATING 5 9 5 CHANGING THE 5 9 6 10 REMOVING DATA FROM eBase REMOVING 10 1 REMOVING EN
52. ON RELATIONAL ENTITIES 7 3 Users Manual eShell Qualifying the Columns or Rows MATRIX SELECT format select list FROM mat name WHERE part 7 4 It is also possible to qualify or constrain the column or row selection with a Matrix WHERE part of the form COLUMNS WHERE part WHERE ROWS IN rorc list where the rorc list is a list of one or more integer row or column numbers depending on the Orientation of the Matrix entity it is a row list for Column major Matrices and a column list for Row major Matrices Example 7 3 Query the KGG Matrix extracting Term Row 2 of col umns 1 2 and 3 eSh MATRIX SELECT 2 FROM KGG WHERE COLUMNS IN 1 2 3 lumn Major Compressed Real Double Precision Symmetric 6 Rows 6 Columns Density 52 0 lumn 2 Selected Row s lumn 3 Selected Row s 400 000 Note that there are no row identification numbers printed In fact the display options may not be specified when the WHERE part is present When the WHERE part is used the requested rows are printed using the FULL format See Chapter 12 for a description of the ways in which you can control the format of the Matrix query RETRIEVING DATA FROM NON RELATIONAL ENTITIES eShell Users Manual FREEFORM ENTITIES This section describes the commands that you may use to retrieve data from Freeform entities These commands are similar in nature to those available for querying Matrix entities The FREEFORM
53. S Sample eBASE database 1 18 Schema Altering for existing Relations 9 6 Components 1 5 Defining for new Relation 3 1 Description 1 2 Schematic Freeform entity 1 6 Schematic Stream entity 1 6 Screen output from query 4 3 Screen output from XY plotter 5 4 Script file Using variables 11 2 Security 1 16 SELECT DIFFERENCE eQL command 4 18 SELECT eQL command 4 1 SELECT INTERSECTION eQL command 4 18 SELECT UNION eQL command 4 18 Selecting values in a set 4 6 Set Definition 4 6 5 10 SET ACTIVE WINDOW eQL command 5 2 SET ARCHIVE command 11 2 Index 6 eShell SET eQL commands BREAK 12 5 COLSPACE 12 5 COLUMN 12 2 FLOATWIDTH 12 6 INTWIDTH 12 6 LINEWIDTH 12 5 PAGELENGTH 12 5 SHOW 13 3 TOLERANCE 13 2 UNDERLINE 12 3 SET FOOTER eQL command 12 4 SET HEADER eQL command 12 4 SET INTERFACE eQL command 11 3 SET PASSWORD eQL command 1 16 SET REPORT eQL command 11 3 SET SCRIPT eQL command 11 1 SHOW 1 13 SHOW eQL command 13 3 Size of database limitations 1 18 SOME option in WHERE clause 4 6 Sorting SELECTed data 4 12 SOLlanguage 1 1 START eOL command 1 10 Storage mode Compressed 1 5 Uncompressed 1 5 Stream entities Attributes of 3 6 Creating 3 6 Defined 1 6 Directory entry 2 4 Inserting data values 8 5 Inserting new data values 8 5 Schematic 1 6 Updating 9 5 Updating data values 9 5 STREAM SELECT eOL command 7 7 Subdirectories 2 2 Subquery Inrelational INSERT 8 2 Inrelational UPDATE 9 3 Specifying in a SELECT 4 13 Subscripte
54. SE 5 5 2 6 RELATIONS WITH INDEXED ATTRIBUTES 2 7 RELEASING ASUBSCRIPTED VERSION 2 8 MANIPULATING ENTITIES 0 0 00 a ee 2 8 3 CREATING eBase ENTITIES CREATING RELATIONS lll sss sss s sss 3 1 THE NULL FIELD CONCEPT llle sss ee 3 3 GREATING MAT RICES ee eee ah tee a dude dedo 3 3 CREATING FREEFORM ENTITIES 3 5 CREATING STREAM ENTITIES 3 6 CREATING SUBSCRIPTED ENTITIES aaau a aaa 3 6 ii TABLE OF CONTENTS eShell Users Manual 4 RETRIEVING DATA FROM RELATIONS THE SELECT COMMAND 4 1 THE OUTPUT FORMAT 2 24522 sss s s sono 4 3 ATTRIBUTES WHICH ARE 4 3 REFERENCING A PATH DURING 4 3 QUALIFYING THE SELECTION 4 4 SELECTING FROM A SET 4 ix kk RISE ee RE eee db bog ee n 4 6 GOMPARING TO ASET 222 doxes jest eee mul a wee Roe ae Pea ea dad 4 6 USING ARITHMETIC EXPRESSIONS 2s 4 6 THE JOIN OPERATION ira os os hos 4 8 GROUPING DATA DURING THE 5 4 11 SORTING DATA DURING THE 5 4 12 THE SUBQUERY v rss tee ph
55. STR 2 4 Entries There are 2 Subscripted Versions The resulting description shows the existing subscripts and the entity class To then obtain the specific information about one of these its sub script is explicitly included in the command DIRECTORIES AND ENTITIES 2 5 User s Manual eShell DESCRIBING DATABASE ENTITIES To determine information about the entities on the eBase database you use the command DESCRIBE ent name where ent name may be the fully qualified name of a database entity of any class Gl Example 2 9 From the root directory move to the subdirectory MODEL and request descriptions for Relation PSHELL Matrix KGG Stream STRM and Freeform FREE eSh gt CD MODEL eSh DESCRIBE PSHELL Relation TESTEB MODEL PSHELL Schema is Attribute Descriptor MID PERI Current Contents 3 Entries The meaning of the attribute type length Len Null specifier and the Descriptor is presented in Chapter 3 eSh DES KGG Matrix TESTEB MODEL KGG Column Major Compressed Real Double Precision Symmetric 6 Rows 6 Columns Density 44 4 The Matrix description indudes information about the Orientation Storage Mode the Numeric Type of the terms in the Matrix the Shape of the Matrix and its size and density The density is the ratio of the number of stored terms to the total possible terms and it indi cates the amount of data compression that has been performed
56. Select Command Data can be selected from Freeform entities if they are Schematic Recall from Chapter 1 that Schematic Freeform entities are those which have a single Numeric Type for all records within the entity The general form of the Freeform query command is FREEFORM SELECT select list FROM free name WHERE part The select list allows you to select either all of the Data Values within a Record of the Freeform or to select only specific values FREEFORM SELECT select list FROM free name select list WHERE part value list where value list is a list of the Data Value sequence numbers that you wish to print In the usual manner all values can be selected by using the asterisk shorthand notation ree name is the name of the Freeform entity that you are querying The WHERE part described in the next section allows you to specify additional selection constraints Example 7 4 Query the Freeform entity TESTFREE and print the first and third records eSh FREEFORM SELECT FROM TESTFREE WHERE RECORDS IN 1 3 Real Single Precision 5 Records 50 Data Values in Longest Record 1 10 Data Values 1 00000 2 00000 3 00000 4 00000 Record 3 30 Data Values 3 00000 6 00000 9 00000 12 0000 RETRIEVING DATA FROM NON RELATIONAL ENTITIES 7 5 Users Manual eShell Qualifying the Records FREEFORM SELECT 7 6 select list FROM free name WHERE part It is also possible to
57. TION 4 2 Ao Pee Eos nh dedes e Xa e genu ig Goals 1 2 DIRECTORY HIERARCHY 1 3 SUBSCRIPTED ENTITIES 1 4 THE MULTISCHEMATIC MODEL ENTITY CLASSES 1 4 Relational Entities 2 es 1 5 areas aa Re ee Ge AIR eee BS a OA Be E RU 1 5 Ereetorm Entities os foe ks aie Gen oe eye Re Sok CE Vee eG 1 6 Stream Entities o ae AE Sted hoe AO a X eg aoe dia 1 6 SYNTAX OF COMMANDS 1 7 lt 1 7 Keywords ula ee Reo Ro XO CE ia Gg 1 7 Abbreviating Keywords 2 ees a ras les 1 7 Simple Metasymbols 1 7 Optional Command Parts dus oe ed E yv Oop aed xcu x UR Pa ag oe 1 7 Command Part 1 8 Metasymbol Suffixes 1 8 Complex Metasymbols 1 8 Important Information lll ss 1 9 NAMING eBase 6 1 9 Basic Naming Rules 2 a llle 1 9 TABLE OF CONTENTS i User s Manual eShell Path Naming Rules 1 9 Entity Naming Rules 2
58. TRIES FROM 5 10 2 REMOVING COLUMNS OR ROWS FROM MATRICES 10 3 REMOVING RECORDS FROM FREEFORM ENTITIES 10 4 11 FILE ENVIRONMENT COMMANDS THE SGRIPTSFILE ie iiia Rum auna DEG A elke uk WO ae pde ue A 11 1 THE ARGHIVE EIEE 4 iu nio ERREUR ERE UE EUR ORE tas Rn 11 2 THE REPORT EIBE 3 ERES a wa EC Y EUR OD ng 11 3 THENTERFAGCEFIEE e SEC moe mom uel DUE ERE S SG eg 11 3 EXPORTING AND IMPORTING DATABASES 11 4 12 REPORT GENERATION FORMATTING COMMANDS 12 1 COLUMN LABELS 5 12 1 PAGE TITLES cUm XR ARDOR ERU x GS xen do TR atn 12 4 GROUPING 5 12 5 PAGE CONTROL COMMANDS rs 12 5 TABLE OF CONTENTS eShell Users Manual 13 UTILITY FUNCTIONS DIRECTORY TREE 22 3 2440 28404 28 e E e Che Ree 13 1 TOLERANCE FOR FLOATING POINT 5 5 13 2 ONLINEHELP 45 ina MA s Ee do e e P Ux deas ci A 13 2 ENVIRONMENT SETTINGS 13 3 A eQL COMMAND SUMMARY A 1 Chapter1 UsingeShell 1 2 Chapter 2 Creating and Maintaining 1 3 Chapter Creating Database
59. abase This organization is best illustrated by an example illustrated in Figure 1 3 Suppose there is a corporate product called JET An eBase database will be used as a repository for all of the engineering activities that will be performed for this product The data for JET has been partitioned into three subdirectories DESIGN ANALYSIS and TEST The ANALYSIS sub directory has also been divided into three directo ries one for aerodynamic analyses AERO one for finite element analyses FEA and one for propulsion analyses PROP The FEA directory has also been partitioned into three subdirectories The first GEOMETRY contains two Entities which define finite element model DESIGN AERO GEOMETRY nones euements INTRODUCTION ANALYSIS FEA SOLVE LOADS Figure 1 3 Typical Data Organization TEST PROP PHYSICAL BOUNDS MATERIALS 1 3 User s Manual SUBSCRIPTED ENTITIES eShell ing data These are called NODES which contains grid point coordinate data and ELEMENTS which contains data defining the finite elements in the model In addition to the geometric data there are other physical data stored in subdirectory PHYSICAL for the finite element model such as material properties MATERIALS and the boundary conditions imposed on the model BOUNDS Finally there is data required for the solution of the analysis such as environmenta
60. al eShell Example 12 1 Query the QUAD4 Relation eSh SELECT FROM QUAD4 4 Entries Selected Any or all columns of the query results may be titled by using the com mand SET COLUMN attribute name column options where column options are a list of one or more options describing the manner in which the column will be printed These options include column option heading info format info justification TEMP CLEAR Each of these options will be described in detail below When you change the title of an attribute this change remains in effect for your entire eShell session or until you issue the SET COLUMN command with the CLEAR option If you want a title to remain in effect for only the next query you may specify the TEMP option when you issue the SET COLUMN com mand The heading info is a string defining the title that you wish placed on the column Its format is column option heading info string format info heading info LABEL lan undc justification TEMP CLEAR where a string may be any sequence of characters with or without embedded blanks A mu1ti line title is specified by separating the lines with the slash character as will be shown in the next example Should the slash character itself be wanted in the label then two consecu tive slashes are entered The optional justification parameter speci fies the manner in which the titl
61. all of the physical data associated with that entity including any Indexes it may have This com mand is COPY entity name 1 TO entity name 2 ALLVER where the ALLVER option allows all subscripted versions of the entity to be copied at one time You may change the name of an entity or all of its versions with the RENAME command RENAME entity name 1 TO entity name 2 ALLVER It is sometimes useful to create a new name for an entity or all of its versions This is done with the ALIAS command ALIAS entity name TO alias name ALLVER The ALIAS command may not be used across databases Finally there are two commands which allow you to convert a Matrix entity from one Storage Mode to another This is done using COMPRESS mat name 1 TO mat name 2 ALLVER UNCOMPRESS mat name 1 TO mat name 2 ALLVER For all of these commands you may specify the Basic Name of an entity if you are operating on all Subscripted versions of it Naturally you may also include a Subscript to explicitly select just one version DIRECTORIES AND ENTITIES eShell Users Manual The ALIAS command does not make any physical copy of the data it simply defines new name a1ias name and Link Components which share the same data component as entity name This is illustrated in Figures 2 1a and 2 1b This results in several side effects If you modify the information in the data component of DATA then these changes will appear in the ali
62. and values for Matrix entities which use the COMPRESSed Storage Mode The next example shows how a Matrix column may be updated Finally the rorc_id is the column or row identification number that will be updated For the Column major Orientation it indicates a col umn and for the Row major Orientation a row 9 3 User s Manual eShell Example9 5 Copy Matrix entity KGG to NEW KGG and change NEW KGG 3 3 to the value 20 0 Query the original value and verify the change eSh COPY MODEL KGG TO NEW KGG Entity Copied eSh MATRIX SELECT 3 FROM NEW KGG WHERE COLUMNS IN 3 Column Major Compressed Real Double Precision Symmetric 6 Rows 6 Columns Density 52 0 Column 3 Selected Row s 500 000 eSh UPDATE MATRIX NEW KGG 2 SET VALUES AT TERM 3 TO 20 0 WHERE COLUMN 1 Column Updated in TESTEB TUTOR NEW KGG eSh MATRIX SELECT 3 FROM NEW KGG WHERE COL IN 3 Column Major Compressed Real Double Precision Symmetric 6 Columns Density 52 0 Column 3 Selected Row s 20 0000 RESTRICTIONS ON MATRIX UPDATING If a Matrix entity has been created with the COMPRESSed Storage Mode then only terms that were initially placed in the Matrix can be updated For the UNCOMPRESSed Storage Mode this is not a problem because all of the terms exist by definition An attempt to update data in the former case will lead to an error condition as shown in the next example Example 9 6 Set NEW 1 5 to
63. aphs or plots from data which you retrieve from Relations The flexibility and op tions available for the plotting of retrieved of data are as complex as those of the query This Chapter is organized in the manner of Chap ter 4 such that successively more advanced uses of the XYPLOT com mand are shown and illustrated by many examples The graphics functions are available only for Unix workstation versions of eShell under the X Windowing System THE PLOTTING WINDOWS of the plots that you create are drawn in one or more Graphic Win dows You can control the number of these windows and the plots that each of them contains For efficiency each plot that you create is saved temporarily during your eShell session This makes it possible for you to recover a plot that you may have deleted previously Because the data are saved you are not required to recreate the query that was used for creating earlier plot GRAPHING RETRIEVED DATA 5 1 Users Manual eShell Selecting the Plot Window The plot windows are independent graphic display windows You may have any number of display windows open at a given time When you create your first plot Plot Window 1 is created and your plot appears in this window This is called the Active Window You may define a new plot window with the command SET ACTIVE WINDOW TO plot win id where plot win idrepresents the number of the active plot window If p1ot win id already exists then any new pl
64. as MYDATA as well If you PURGE either entity then the name component will be removed from the database but the data com ponent will remain and may be referenced by the a1ias name as shown in Figure 2 1c Figure 2 1 Effect of ALIAS Command ALIAS DATA MYDATA PURGE DATA A A DATA MYDATA MYDATA Link Link Link Data Data Data Component Component Component a Initial State b Link Created by c Original Name Removed of Database ALIAS Command but ALIAS Link Remains DIRECTORIES AND ENTITIES 2 9 User s Manual This page is intentionally blank eShell DIRECTORIES AND ENTITIES eShell Users Manual 3 CREATING eBase ENTITIES CREATING RELATIONS CREATE RELATION rel name schema list LIKE old rel CREATING eBase ENTITIES In addition to using an eBase database created by a software application that uses the eBase applib tools you may also create a new database or add new entities to an existing one This Chapter describes the com mands and techniques for performing these operations A new Relation may be added to the eBase database and as will be seen in Chapter 8 data inserted into it The command to do this is CREATE RELATION rel name schema list LIKE old rel The rel name is the entity name to be created and schema listisa list of one or more schema terms These terms specify the attributes which define the Relation and their data
65. ate Re st at eur ie GG ee a ar diay ee ts 4 13 GROUP OPERATORBS 5 me Bead ete A ae Boe Rid BE Byles net dos Hk ee 4 15 INTERSECTION UNION AND 4 18 5 GRAPHING RETRIEVED DATA THE PLOTTING WINDOWS 5 1 Selecting the Plot Window 2 0 2 ee 5 2 THE PLOTTING COMMANDS 5 2 THE XYPLOT COMMAND 5 2 THE GRAPH ELEMENTS 5 4 Symbols and Lines aoaaa 5 4 TT iu same a a Shee oh Atala ar Sak ea x MER LES Y Ba TP 5 4 Customizing the 5 5 REFERENCING A PATH DURING 5 7 QUALIFYING THE SELECTION sss sse ee 5 8 SELECTING FROMA SET a a E a sss es 5 10 USING ARITHMETIC 551 5 5 11 The ADDCURVES 5 11 The MXYPEOT Commiahd von d doe ee ere eos e deme amp a e RI SUUS 5 13 6 INDEXING RELATIONAL ENTITIES THE INDEX GONCEPT zou Rh Re ee BA SE eae ge cR 8 6 1 CREATING THE INDEX hs os os sos ss 6 1 IMPROVING QUERY PERFORMANCE 6 3 INDEX PERFORMANCE aa E aoaea sss ss ho os osos 6 4 INDEX OVEREEAD za a satyr Aa ana ine i Per ube Ras one ee a ee PR e Tod vins 6 6 PURGING AN I
66. ate a Matrix partition which can be an equivalent operation to deleting the rows of a Matrix then the EXTRACT MATRIX command can be used When you DELETE from a Matrix entity the topological Shape may be changed For example in Example 10 3 the Symmetric Shape was changed to Rectangular after the column deletion You must use the SET MATRIX SHAPE command to make the Shape consistent with the data in the entity This is only important if the Matri ces will be used with eBase matlib When you DELETE one or more Columns or Rows from a Matrix entity F all subsequent Columns or Rows are renumbered Therefore you cannot reference them by their original number REMOVING DATA FROM eBase 10 3 User s Manual eShell REMOVING RECORDS FROM FREEFORM ENTITIES Finally you may remove an entire Record from a Freeform entity with the command DELETE FROM FREEFORM free name list where the ree name is the name of an existing Freeform entity and the list identifies the Records to be deleted Example 10 4 Delete the odd numbered Records from DEL FREE a copy of Freeform FREE and confirm the result using the DESCRIBE command COPY MODEL TESTFREE TO DEL FREE 1 Entity Copied DELETE FROM FREE DEL FREE 1 3 5 Enter YES to delete 3 Records leaving 2 Records YES 3 Records Deleted from TESTEB TUTOR DEL FREE DESCRIBE DEL FREE Freeform TESTEB TUTOR DEL FREE 2 Records Longest Record is 40 When
67. ath Creates a new directory CD path Changes or displays current working directory RMDIR path Removes an existing directory ALL RELATION MAT DIRECTORY path FREEFORM pr STREAM DIRECTORY Requests a directory listing DIRECTORY ent name ALLVER Ee SUMMARY Requests a directory listing for entities DESCRIBE entity name Provides a description of any of the entities contained within the eBase database RELEASE ent name Specifies a particular subscripted version of an entity to be the Released Version A 3 User s Manual eShell UNRELEASE ent name Deletes the Released Version of an entity COPY entity name 1 TO entity name 2 ALLVER Makes a physical copy of one or more subscripted versions of an entity RENAME entity name 1 TO entity name 2 ALLVER Renames one or more subscripted versions of an entity ALIAS entity name TO alias name ALLVER Creates a new name or alias by which one or more subscripted versions of an entity may be referenced COMPRESS mat name 1 TO mat name 2 ALLVER To transform an UNCOMPRESSED Matrix entity to a COMPRESSED Ma trix entity UNCOMPRESS mat name 1 TO mat name 2 ALLVER To transform a COMPRESSED Matrix entity to an UNCOMPRESSED Ma trix entity Chapter 3 Creating Database Entities 4 This Chapter describes the commands and techniques for adding new entities t
68. ation THISTORY resides in the direc tory BIGPLANE WING The following methods may be used to plot the Relation XYPLOT TIME T1 FROM BIGPLANE WING THISTORY Or CD BIGPLANE WING XYPLOT TIME TI FROM THISTORY or DEFINE PATH bigplane wing XYPLOT TIME T1 FROM amp PATH THISTORY Refer to Chapter 2 for a detailed discussion of path names GRAPHING RETRIEVED DATA 5 7 Users Manual eShell Table 5 1 Logical and Relational Operators OPERATOR PURPOSE LOGICAL TRUTH TABLES AND Logical conjunction AND T F OR Logical disjunction T T F NOT Logical Negation F F F Equality lt gt Inequality lt Less than gt Greater than OR lt Less than or equal gt Greater than or equal QUALIFYING THE SELECTION 5 8 You may also create graphs for only those entries in a Relation that satisfy a certain condition or combination of conditions This is accom plished by using the following variation of the XYPLOT command XYPLOT x and y list FROM rel name WHERE search condition where a search condition is identical to that of the Relational query Example 5 6 Plot the 1 and T3 components in Relation GRID that have values greater that 0 0 First clear the values of XMIN and XMAX that you set in Example 5 4 eSh CLEAR XMIN eSh CLEAR XMAX eSh XYPLOT TIME T1 T3 FROM THISTORY WHERE T1
69. ay attributes 3 3 Examples Describe Describing a Matrix entity 2 6 Describing a Relational entity 2 6 Describing a single subscripted entity 2 7 Describing a Stream Entity 2 6 Describing an Freeform Entity 2 6 Describing an indexed Relation 2 7 Examples Directories Changing the working directory 2 2 Users Manual Creating 2 2 Default directory listing 2 3 Directory listing 2 4 Entity directory listing 2 5 Entity version directory listing 2 5 Released entity directory listing 2 5 Removing a directory 2 3 Examples eSHELL Editing a command 1 14 Multiple line command entry 1 13 Running the program 1 12 1 13 Saving a command in a file 1 15 Using a command file with variables 1 15 11 2 Using symbol substitutions 1 15 Examples Files Interface file writing to 11 3 Examples Freeform Deleting records 10 4 Inserting a record 8 4 Printing 7 5 Updating 9 5 Using a WHERE clause 7 6 Examples Index Creating a unique index 6 2 Creating an index for a Relation 6 2 Index performance for a Relation 6 5 Purging an index of a Relation 6 6 Using a unique index 6 2 Examples Matrix Deleting columns 10 3 Inserting a column 8 3 Printing BAND 7 3 Printing FULL 7 3 Updating 9 4 Updating illegally 9 4 Using a WHERE clause 7 4 Examples Relation Altering the schema 9 6 Arithmetic expressions in select 4 7 Arithmetic expressions in XY plot 5 11 Deleting entries 10 2 Difference of two Relations 4 19 Group o
70. ay toggle this option on or off for either or both axes Axis Values and Ticmarks The number of values and ticmarks placed on the axes may be controlled using XDIV SET YDIV vo ine where inc is the increment value for the selected axis Drawing Grid Lines You may request that grid lines be drawn from each of the ticmarks on an axis with the command ON SET GRID TO Drawing the Axes You may toggle the drawing of the axes with the command ON SET AXIS TO b GRAPHING RETRIEVED DATA eShell Users Manual Example 5 4 Repeat example 5 3 but this time create a blow up be tween TIME values of 0 12 and 0 14 adding titles to the graph eSh SET XMIN TO 0 12 eSh SET XMAX TO 0 14 eSh XYPLOT TIME T1 T3 FROM THISTORY which results in the graph with the graphics elements annotated Transient Response 0 4 T1 T3 2 0 3 YMAX 0 2 GRID ie 0 1 2 Jem S 0 i a Q 5 0 1 y 0 2 YMIN XMAX 0 3 b XMIN X 0 4 0 12 0 125 0 13 0 135 0 14 REFERENCING A PATH DURING THE QUERY The rel name specified in the FROM part of a query may include a full path name in addition to a simple entity name Alternately you may set a default path prior to the query or you may define a global symbol that is used in the name These are shown in the following example Example 5 5 Suppose that the Rel
71. base eSh RMDIR ANALYSIS FEA eSh RMDIR ANALYSIS Note that all entities must be PURGEd from the directory before it may be removed See Chapter 10 There is an eQL command available that is used to determine informa tion about the contents of a directory There are two forms of the com mand to do this The first is used for complete directories and the second is used for entities These are described in the following sections Using a Path Specification To obtain a directory listing for a selected directory you use the com mand ALL RELATION MATRIX DATE DIRECTORY path FREEFORM pr STREAM DIRECTORY where path is a valid Path name If the path is omitted a listing of the entities in the current Working Directory is printed as illustrated in the example below Example 2 4 While in the root directory print the directory listing for the TESTEB database eSh DIR Directory TESTEB Class Size DIR 2 Entities MODEL DIR 3 Entities RESULT DIR 3 Entities Directory Contains 3 Subdirectories DIRECTORIES AND ENTITIES 2 3 User s Manual 2 4 eShell In this case there are no entities in the root directory However a listing of the subdirectories within a directory are shown along with a count of the number of entities in each The next example shows the results ob tained when a path is specified in the DIR command Example 2 5 List each direct
72. characteristics Each schema termin this list has the form schema term attrib name attrib type attrib len NOT NULL descriptor The attrib name must follow the valid naming rules The attribute types attrib type that may be selected are shown in Table 3 1 The attrib len parameter is an integer that defines the length of the attrib ute For numeric arrays this is used only when the array has two or more elements It is also possible to specify the NOT NULL option for each 3 1 User s Manual 3 2 v eShell Table 3 1 Relational Attribute Types attrib type DESCRIPTION attrib len INT Integer Value Length of Array RSP Real Single Precision Value Length of Array RDP Real Double Precision Value Length of Array CSP Complex Single Precision Value Length of Array CDP Complex Double Precision Value Length of Array CHAR Character String Number of Characters attribute The meaning of NULL attributes is discussed later in this Chap ter Finally you may attach a descriptor to an attribute A descrip toris simply text which allows you to provide an amplified description of the meaning of the attribute It is necessary for you to have the AD MINISTRATION privilege in order to create a Relation The Relation may also use the schema previously defined for an existing Relation old rel by using the LIKE clause The use of the CREATE RELATION command is quite simpl
73. cs Inc All rights reserved eSh OPEN MY EB WITH ADMIN eSh Enter ADMINISTRATION Password MAGIC eBase MY EB Open with ADMINISTRATION Privilege Your eQL Commands END eShell Ended at 09 30 dd mmm yy Elapsed Time 00 16 21 CPU Time 00 02 21 Note that the password is not a security measure for entering the eShell program but the password under which eBase databases will be ac cessed eShell then verifies that the password allows the access you have requested You may use two or more eBase databases simultaneously Each data base may be opened with any privilege level The sequences of events shown in Example 1 1 occurs each time you open a database as shown in the following example 1 12 INTRODUCTION eShell Users Manual Example 1 2 Execute the eShell program for two eBases hell eShell Version 20 0 dd mm yy 14 22 Copyright c 1992 1997 Universal Analytics Inc All rights reserved OPEN FOO WITH ADMIN Enter ADMINISTRATION Password MAGIC eBase FOO Open with ADMINISTRATION Privilege OPEN BAR WITH READ ENTER READ PASSWORD SCRT eBase BAR Open with READ Privilege of the operations described in the remainder of this manual may now be performed You may terminate work on a given database by simply entering the command CLOSE database name DELETE The DELETE option will delete all of the database physical files from your host computer To use this op
74. cteristics are specified with MODE mode type TYPE num type mat attr term gt 5 E shape ROWS COLUMNS number of rorc Table 3 2 presents the available options for the Storage Mode mode type and Numeric Type num type The Matrix num types are somewhat different from those of Relational entities The num ber of rorc depends on the Storage Mode The eBase Matrix storage options allow one dimension of a Matrix to be fixed and the other dimension to be dynamic In the case of the Column major Orienta tion the number of columns is dynamic while the number of rows is fixed For Row major matrices the opposite is true the number of rows is dynamic and the number of columns static As a result if your Matrix is stored in Column major mode then the number of Rows is entered if it is in Row major form then the number of COLUMNS is en tered In both cases these are entered as an integer value Note that the ADMINISTRATION privilege is also required to create a Matrix and that a LIKE dause may be specified to use the attributes of an existing Matrix Table 3 2 Matrix Attribute Types SYMBOL KEYWORD DESCRIPTION COMPRESS Compressed Storage Mode mode type UNCOMPRESS Uncompressed Storage Mode INT Integer Terms RSP Real Single Precision Terms num_type RDP Real Double Precision Terms CSP Complex Single Precision Terms CDP Complex Double Precision Terms RECTANGULAR Aij i
75. d Entities 2 4 Creating 3 6 Description 1 4 Dimensionality 3 6 DIR results 2 5 Substitution variables 11 1 SUM operator 4 15 Syntax of eQL commands See eQL command syntax System interface manual 1 1 T Term of Matrix 1 5 Tolerance for floating point values 13 2 TREE eQL command 13 1 eShell Users Manual Tree of directory 13 1 Inscriptfile 11 2 Truth tables 4 4 Virtual attributes 4 6 U W uaidoc program 1 11 WHERE clause Uncompressed storage mode 1 5 Comparing to a set 4 6 UNDEFINE eQL command 1 2 1 15 Contained in a 4 6 Union of relations 4 18 Definition of 4 4 UNIQUE index of Relation 6 1 In Relational UPDATE 9 2 UNRELEASE eQL command 2 8 Joining relations 4 9 UPDATE eQL command 9 1 Subqueries in 4 13 UPDATE FREEFORM eQL command 9 4 Using ALL SOME or ANY 4 6 UPDATE MATRIX eQL command 9 3 Using IN and NOTIN 4 6 5 10 UPDATE STREAM eQL command 9 5 Working directory 2 2 WRITE privilege V Description 1 16 Variable length records 1 6 X Variables XYPLOT eOL command 5 2 Index 7 User s Manual eShell This page is intentionally blank Index 8
76. e curve is drawn for each unique value of the specified param Chapter 6 Indexing Relational Entities eQL COMMAND SUMMARY CREATE UNIQUE INDEX ON rel name attribute list Creates an index for one or more attributes of a Relation PURGE INDEX ON rel name attr list Deletes a previously created index from a Relation A 7 User s Manual eShell Chapter 7 Retrieving Data from Non Relational Entities This Chapter describes commands that may be used to retrieve data from Matrix Freeform and Stream entities MATRIX SELECT format select list FROM mat name WHERE part Allows selected portions of a Matrix to be displayed in a specified for mat format gt Specifies the format of the Matrix selection results term list select list Specifies the terms within rows or columns that will be selected from the Matrix COLUMNS WHERE part WHERE ROWS IN rorc list Restricts the Matrix selection to terms from specific rows or columns FREEFORM SELECT select list FROM free name WHERE part Allows selected portions of a Freeform entity to be displayed value list select list gt Specifies the Data Values to be selected from a Freeform entity WHERE part WHERE RECORD num RECORDS IN record list Restricts the Freeform selection to specific Records STREAM SELECT select list FROM free name Allows selected portions of a Strea
77. e Orientation of the Matrix Recalling the descrip tion of Matrix Orientation presented in Chapter 1 for matrices which are stored in the Column major Orientation the number of rows is fixed while its number of columns is dynamic Similarly for matrices which are stored in the Row major form Orientation the number of columns is fixed while its number of rows is dynamic In the former case row deletion is not allowed and in the latter case column dele tion is not allowed To delete one or more selected columns or rows from a Matrix the command DELETE FROM MATRIX mat name list is used where the mat name is the name of an existing Matrix entity and the list identifies the columns or rows to be deleted eShell automat ically determines the Orientation and deletes the data accordingly Example 10 3 Delete the odd numbered columns from DEL KGG a copy of Matrix KGG Verify the results by querying the Matrix eSh COPY MODEL KGG TO DEL KGG Entity Copied eSh DELETE FROM MATRIX DEL KGG 1 3 5 eSh Enter YES to delete 3 Columns leaving 3 Columns YES 3 Columns Deleted from TESTEB TUTOR DEL KGG eSh MATRIX SELECT BANDED FROM DEL KGG Column Major Compressed Real Double Precision Symmetric 6 Rows 3 Columns Density 44 4 Rows 1 throug 00000 02 3 00000 02 lumn 2 Rows 3 throug 00000 02 7 00000E 02 lumn 3 Rows 5 throug 00000E 03 1 10000E 03 If you wish to cre
78. e as shown in the next example Example 3 1 Create a new directory TUTOR and in this directory create a Relation 0452 with the same schema as the Relation Q4STR 2 contained on the TESTEB database MKDIR TUTOR CD TUTOR CREATE REL 0452 EID INT SIGX RSP SIGY RSP TAUXY RSP or CREATE REL 0452 LIKE RESULT Q4STR 2 The TUTOR Directory will be used for many of the examples in the remainder of this manual CREATING eBase ENTITIES eShell Users Manual Attributes that are defined as arrays those having attrib len greater than one are intended to store data that is exclusively used on an all or nothing basis This might be the case for instance when storing transfor mation matrices Example3 2 In subdirectory TUTOR create a new Relation called TRANS Each entry contains an identification number TID and a small 3x3 Matrix called T Assume that the Matrix T will only be accessed in its entirety for computational purposes and can thus be stored as an array of RSP values Also add appropriate descriptors to the attributes eSh CREATE RELATION TRANS 25 TID INT Transformation ID Number 3 T RSP 9 Transformation Matrix THE NULL FIELD CONCEPT CREATING MATRICES CREATING eBase ENTITIES Many Relational databases indude the concept of a NULL field within an entry of a Relation This feature is useful for entities which have many attributes which can be logically grouped
79. e command 1 13 ADDCURVES eQL command 5 11 ADMINISTRATION privilege Description 1 16 Adobe Acrobat reader 1 11 ALIAS eQL command 2 8 ALL option in WHERE clause 4 6 ALTER eQL command 9 6 AND function 4 4 ANY option in WHERE clause 4 6 Archive file 11 2 Arithmetic expressions in SELECT 4 6 Arithmetic expressions in XY plot 5 11 Arithmetic functions 4 8 Array attributes Formatting in reports 12 6 In Relations 3 3 Attributes Arraysin query 4 3 Arrays in Relations 3 2 Description 1 5 NOT NULL 3 2 8 2 NULL 3 3 Of Matrix entities 3 4 Of Relational entities 3 1 Of Stream entities 3 6 Virtual 4 6 Attributes Selecting DISTINCT 4 2 AVG operator 4 15 B BAND Matrix print option 7 3 Basicname 1 9 C Case insensitivity 1 11 CD eQL command 2 2 CHANGE command line eOL command 1 14 Changing databases while in eSHELL 1 12 Changing directories 2 2 eOL commands 5 2 CLEAR eQL command 5 2 CLOSE eQL command 1 2 1 13 Column major orientation 1 5 Command file 11 1 Comparing values in a set 4 6 ALL 4 6 ANY 4 6 SOME 4 6 Compressed storage mode 1 5 COPY eQL command 2 8 COUNT operator 4 15 Counting entries in a relation 4 17 Index 1 User s Manual CREATE eQL commands FREEFORM 3 5 MATRIX 3 3 RELATION 3 1 STREAM 3 6 CREATE INDEX eQL command 6 1 Creating a new database 1 12 Creating directories 2 2 Creating new entities Freeforms 3 5 Matrices 3 3 Relations 3 1 Streams 3 6 Current position 1 14 D Data component
80. e new attributes being added to re1 name Example 9 9 Using the Relation NEW created previously add a new attribute to this entity which will be used to contain the distance of the grid point from the origin DIST asa real single precision value Verify that the attribute was added eSh ALTER NEW GRID ADD DIST RSP Attribute DIST Added to NEW GRID eSh DESCRIBE NEW GRID Attribute Z DIST Current Contents 10 Entries It is necessary to have ADMINISTRATION privilege in order to ALTER the schema of a Relation Note that this operation can be quite expensive because a new Relation is lt P created and the contents of the original are copied to the new one with the specified attributes added The fields for all new attributes are defined as NULL following the opera tion In order to add data to these fields the UPDATE or INSERT com mands must be used 9 6 UPDATING ENTITY DATA eShell Users Manual Example 9 10 Query the Relation NEW for values of GID less than 4 Then update the DIST field with the distance value and perform the same query on the result SELECT FROM NEW GRID WHERE GID 4 0 00000 1 00000 1 00000 1 00000 2 00000 1 00000 UPDATE NEW GRID SET DIST SQRT X 2 Y 2 2Z 2 10 Entries Updated SELECT FROM TO NEW_GRID WHERE GID lt 4 0 00000 H 00000 1 00000 1 00000 00000 1 41421 2 00000 00000 2 23607 EB database to H
81. e will be justified over the column 12 2 REPORT GENERATION eShell column option gt heading info format info justification TEMP CLEAR column option gt heading info format info justification TEMP CLEAR REPORT GENERATION Users Manual It may be selected as LEFT justification 4 RIGHT CENTER If not given the default justification is used i e LEFT for string data and RIGHT for numeric data Example 12 2 Change the headings for the QUAD4 query so that EID becomes ELEMENT ID NUMBER and PID becomes PSHELL ID eSh SET COLUMN EID LABEL ELEMENT ID NUMBER Permanent Report Column EID Created eSh SET COL PID LABEL PSHELL ID Permanent Report Column PID Created eSh gt SELECT FROM QUAD4 ELEMENT ID NUMBER PSHELL ID 4 Entries Selected The format info specifies the exact format that you wish to use in printing the column Its form is a subset of Fortran and may be Iw Fw d Ew d j Dw d Aw Gw d format info FORMAT where w represents the total field width in characters and d the number of decimal places The user may also control the character used to under line attribute names This is done using the command SET UNDERLINE TO underline character where the underline character is a single legal character Note that this character must be enclosed in apostrophes If a blank is used for the unde
82. eBase database SET TOLERANCE TO value PERCENT Specifies the tolerance used in comparing floating point numeric values used in query commands HELP command part list Requests additional information about eQL commands SHOW variable class list Provides a summary of current environment variables FILES COLUMNS PAGE VERSION CONFIG OPEN DATABASES variable class list Selects a subset of environment variables A 13 User s Manual This page is intentionally blank eShell eQL COMMAND SUMMARY eShell Users Manual B GLOSSARY GLOSSARY Active Command eShell performs no action until you have entered a complete command including the semicolon This command is called the Active Command Active Plot Window Is a graphics window that may be defined by the user which contains the results of the next plotting command ADMINISTRATION Privilege Is the eBase privilege level which allows a user called the Database Administrator DBA to control the use of the database and the specific access allowed by its users Archive File Atextfile that contains an historical record of the commands entered during an eShell interactive session Specifically it is a copy of commands that have executed successfully If a command has been edited only the final form of the command is archived Those which contained user errors are not put on the archive file The principal purpose of this file is to use it d
83. ed indexed attribute values To see the impact of indexing consider the following example INDEXING RELATIONAL ENTITIES eShell Users Manual Example 6 4 Study the performance of indexes using Relation RESULT BIGREL on the TESTEB database eSh CD RESULT eSh DESCRIBE BIGREL Relation TESTEB RESULT BIGREL Schema is Attribute Current Contents 10000 Entries Now perform a query of BIGREL and observe the elapsed time needed to retrieve the required entry eSh START BIGREL eSh SELECT ATT3 FROM BIGREL WHERE ATT1 10000 1 Entry Selected Next create an index for ATT1 eSh CREATE INDEX ON BIGREL ATT1 Index Created Perform the query again and note the results This has undoubtedly con vinced you of the value of indexing when a Relation will be queried for specific entries If you have Relational entities with a large number of entries many thousands and you are going to perform many queries against the data then create as many Indexes as necessary the access speed up will always be significant and the overhead needed to created the indexes is negligible by comparison INDEXING RELATIONAL ENTITIES 6 5 User s Manual INDEX OVERHEAD PURGING AN INDEX 6 6 eShell There is a certain amount of overhead when you create an index for a Relation You will have noticed this while performing Example 6 4 How ever also note that this o
84. elf There is also a Link Component from the schema to the Data Component eBase is a Multischematic Da tabase This means there are different kinds of schemas Entities which share the same type of schema are grouped into Entity Classes The eBase Entity classes are described in more detail later in this Chapter Although the Entities contain the actual data that is being managed eBase sup ports a hierarchical organization which allows you to specify the levels of data which are compatible with your way of doing business Beyond this eBase provides an Entity Subscript which allows storage of different revisions of the same data classes INTRODUCTION eShell DIRECTORY HIERARCHY Users Manual Figure 1 2 illustrates a typical way in which an eBase hierarchy may be defined The eBase in the figure contains three Directories A direc Figure 1 2 eBASE Directory Hierarchy tory might contain the engineering data for a specific product line or it might contain a subset of such data for a large and complex product Each directory may in turn be composed of one or more Subdirec tories containing related data Each directory or sub directory may contain different data Entities These Entities may be organized in as many additional lev els of directories as needed to fully categorize the data In Figure 1 2 the white boxes represent direc tory hierarchy levels while the shaded boxes repre sent actual data stored in the dat
85. ell Users Manual The MXYPLOT Command Often the data stored in a relation represent repeated sets of values that vary for a given parameter As an example consider the following PARAMETER X Y 1 5 0 10 0 15 0 28 0 42 0 56 0 100 0 101 0 102 0 IN IN FP Je M WIN JW IN jo jo jo jo o jo You would like to create three separate curves represented by the X Y pairs appearing in the relation Each curve will represent a different value of PARAMETER This is done with the command MXYPLOT param x_attrib y_attrib FROM_part WHERE part GROUP part ORDER part As with the other plot commands the x attrib y attrib list and FROM part are required and the other clauses are optional This command results in one curve for each unique value of param re trieved from the specified relation Only one attribute may be specified for the x axis and y axis of the plot The axes are scaled based on the union of all of the plots that will be drawn Example 5 12 In directory plot the relation ROOTS contains data that represent velocity VELO and damping DAMPV curves There are com plete curves for each MODE and for each ITERation in the solution proce dure Plot individual velocity damping curves for each iteration for MODE 5 MXYPLOT NITER VELO DAMPV FROM ROOTS WHERE MODE 5 GRAPHING RETRIEVED DATA 5
86. entry in the Relation Only attributes having data types of INT and CHAR may be used as indexes To index other types of attributes special artifices may be used as described later in this Chapter A UNIQUE index is one in which each Key value is different from every other Key value If the index Key is comprised of multiple attributes although each individual INDEXING RELATIONAL ENTITIES 6 1 User s Manual 6 2 eShell attribute may have a duplicated value the combination of all the attrib utes in the Key must be unique Example 6 1 In Directory called TUTOR make a copy of Relation RESULT Q4S called IDX_Q4S and create an index for IDX_Q4S on attribute CAS MKDIR TUTOR CD TUTOR COPY RESULT Q4S TO IDX Q4S CREATE INDEX ON IDX_Q4S CASE Index Created Indexes may also be used to enforce the uniqueness of one or more attributes in a Relation Consider the following example Example 6 2 Now make a copy of Relation GEOM GRID called IDX GRID and create a unique index for it on attribute GID eSh COPY GEOM GRID TO IDX GRID eSh gt CREATE UNIQUE INDEX ON IDX_GRID GID Index Created If this index has been created then you may not insert data into the Relation which has the same index value as an existing one for the spedified attributes Example 6 3 Add a new entry to Relation IDX_GRID which has GID 1 eSh INSERT INTO IDX GRID 2 VALUES 1 1554 545 9 4 ERR Duplicate Ke
87. eport columns 12 3 Formatting commands Column labels 12 1 Grouping commands 12 5 Page control 12 5 Page titles 12 4 Freeform entities 1 6 Creating 3 5 Directory entry 2 4 Inserting new records 8 4 Records 1 6 Removing data from 10 4 Schematic 1 6 Updating 9 4 Updating records 9 5 FREEFORM SELECT eQL command 7 5 FULL Matrix print option 7 3 Fully qualified entity name 2 1 Index 4 eShell G GROUPing GROUP BY Clause 4 11 Operators 4 15 SELECTed data 4 11 H HELP 1 13 13 2 IEEE Floating Point standard 1 17 See also importing and exporting databases IMPORT eQL command 11 5 Importing databases 1 17 11 4 IN option in WHERE clause 4 6 5 10 Index Creating 6 1 Definition 6 1 Key attribute 6 1 Overhead 6 6 Performance 6 4 Purging 6 6 Query performance 6 3 Unique 6 1 Indexed attributes 2 7 INSERT INTO eQL command 8 1 INSERT INTO FREEFORM eQL command 8 4 INSERT INTO MATRIX eOL command 8 3 INSERT INTO STREAM eQL command 8 5 Integrity 1 17 Interface file 11 3 Formats 11 3 Intersection of relations 4 18 J Joining relations 4 8 Justification Column labels 12 3 Page titles 12 4 K Key attribute See Index Keywords in commands 1 7 L Labels for columns 1 12 12 1 12 2 Limitations database size 1 18 Limitations system 1 17 Link component 1 2 LIST command line eOL command 1 13 eShell LogicalAND 4 4 Logical 4 4 MATLIB 1 2 8 4 10 3 Matrix Inserting new columns 8 3 Matrix att
88. er s Manual eShell INTERSECTION UNION AND DIFFERENCE 4 18 There are three additional Relational operations that are often useful Their primary use is to compare or merge two Relations having ex actly the same schema The intersection of two Relations is the set of entries that occur in both Relations that are identical in all fields The command to perform this operation is SELECT INTERSECTION OF rel name 1 AND rel name 2 AS rel name 3 The INTERSECT command is a special form of SELECT Note that only the distinct entries common to both Relations will result from this com mand and that no WHERE part GROUP part or ORDER part may be used If you wish to save the resulting Relation the optional AS clause is used Both of these facts are true of the next two commands SELECT UNION and SELECT DIFFERENCE as well This is of no significance because the new Relation rel name 3 is created from these com mands It may then be queried in any manner You must have the AD MINISTRATION privilege on the databases containing rel name 1 rel name 2 and rel name 3 Example 4 29 Find the intersection of Relations Q4STR 1 and OASTR 2 eSh CD RESULT eSh SELECT INTER OF Q4STR 1 AND Q4STR 2 No Entries Selected This example verifies that there are no common entries in the two ver sions of Q4STR The union of two Relations having the same schema is defined as the collection of all distinct entries that appear in eit
89. esign engineer to access modify and manage the information in an eBase database interactively eShell accomplishes this by providing the user with a powerful query language called eQL eBase Query Language The eQL language ad heres to the ANSI Standard for Database Language SOL X3 135 1986 as much as practical This standard which addresses relational databases has been extended to accommodate the more powerful features of eBase THE eBase SOFTWARE SUITE INTRODUCTION The suite of eBase products includes O The eBase Shell eShell and Interactive Query Language eQL 1 eBase applib the Application Development Library 3 eBase matlib the Matrix Utility Library There are three manuals which document these products This document the eShell User s Manual Publication EB 001 LJ eBase applib User s Manual Publication EB 003 O eBase matlib User s Manual Publication EB 004 A fourth manual called The Installation Guide and System Support Manual various part numbers provides information describing the 1 1 Users Manual DATA MODELING eBase ORGANIZATION 1 2 Figure 1 1 Entity Components DATA COMPONENT SCHEMA eShell host computer dependent characteristics of all of the UAI software prod ucts eBase applib is a run time library of Fortran subroutines which is an advanced database tool for use in cost effective scientific software devel opment eBase matlib is a similar library of high perfo
90. extend the length of the Freeform Record when you perform the UPDATE FREE operation UPDATING STREAM DATA 057 UPDATING ENTITY DATA It is also possible for you to update any existing Data Item in a selected Stream entity with the command UPDATE STREAM stream name SET position TO value list where the stream name is the name of an existing Stream entity and position is the location of the first Data Item to be changed The value list is a list of one or more values that will replace all of the Data Items beginning with position Example 9 8 Copy Stream entity STRM to UP STRM and change Data Values 110 through 115 to those indicated and verify the change COPY MODEL STRM TO UP STRM 1 Entity Copied UP STREAM UP STRM SET 110 TO 1 1 1 1 1 1 5 Data Values Updated in TESTEB TUTOR UP STRM STREAM SELECT 110 111 112 113 114 115 FROM UP STRM Integer Data Values The UPDATE STREAM command requires the WRITE privilege You may not extend the length of the Stream entity when you perform the UPDATE STREAM operation To do this you use the INSERT INTO STREAM command also described in Chapter 8 9 5 User s Manual eShell CHANGING THE SCHEMA OF A RELATION It is also possible to change the schema of an existing Relation by adding a new attribute toit This is done with the command ALTER rel name ADD new schema list where the new schema list is composed of schema terms already defined in Chapter 3 for th
91. fied plot windows REPLOT plot win id Replots the data is a specified plot window XYPLOT x attrib y attrib list FROM part WHERE part GROUP part ORDER part Selects all or part of a Relation for plotting The WHERE part GROUP part and ORDER part are the same as for the Relational query SET DRAWLINE TO ON OFF SET SYMBOL TO es Selects the drawing of lines and symbols for the graph data SET FTITLE TO text XTITLE 7 TO text FTITLE CLEAR XTITLE 5 YTITLE Allows plot titles to be added and cleared eQL COMMAND SUMMARY eShell Users Manual XMIN SET XMAX CLEAR ym n TO valve i YMAX Allows plot data to be windowed XLOG ON PES YLOG OFF Selects one or two logarithmic scales XDIV YDIV TO inc Controls the number of labeled divions on each axis of the plot ON SET GRID TO on ON SET AXIS TO Control whether a grid is applied to the plot and whether the axes are drawn ADDCURVES x attrib y attrib list FROM part WHERE part GROUP part ORDER part Adds a new curve to an existing plot in the Active Window MXYPLOT param x attrib y attrib FROM part WHERE part GROUP part ORDER part Selects all or part of a Relation for plotting The WHERE part GROUP part and ORDER part are the same as for the Relational query On
92. h have the form attrib term gt Relation name attribute name The second difference appears in the FROM part which now has more than one Relation Indeed it lists all Relations from which the at trib list will be drawn Note that only attributes which appear in more than one Relation must be prefixed by the Relation name The WHERE part specifies that only the entry from Relation QUAD4 with an EID of 1 will be retrieved and then it specifies that if the PID of this entry is the same as the PID in a PSHELL entry join the entries The earlier portion of the SELECT has requested only that the EID PID and MID fields of the resulting joined entry should be printed If there is only a single search condition in the WHERE part and this search condition is equality then the operation is called an Equi join Example 4 13 Join the QUAD4 Relation to the PSHELL Relation and retrieve the element identification number EID prop erty identification number PID and material identifica tion number MID for each element eSh gt SELECT EID QUAD4 PID MID 2 gt FROM QUAD4 MODEL PSHELL WHERE 3 gt QUAD4 PID PSHELL PID 4 Entries Selected RETRIEVING DATA FROM RELATIONS 4 9 User s Manual eShell When you perform a JOIN operation using Relations from more than one Directory you use a special form of the FROM 1ist and the SE LECT list The FROM list specifies the names of the Relations in the form rel
93. he first three data values eSh STREAM SELECT 1 2 3 FROM STRM Integer 1000 Data Values See Chapter 12 for a description of the ways in which you can control the format of the Stream query RETRIEVING DATA FROM NON RELATIONAL ENTITIES 7 7 User s Manual eShell This page is intentionally blank RETRIEVING DATA FROM NON RELATIONAL ENTITIES eShell Users Manual 8 INSERTING DATA INTO ENTITIES This Chapter describes the eQL commands which are available to insert new data into eBase entities ADDING NEW ENTRIES TO RELATIONS INSERT INTO REL rel name proj list value part New data entries can be added to existing Relations with the command INSERT INTO RELATION rel name proj list value part where rel name is the name of an existing eBase Relation The op tional proj_list isa list of attributes of rel_name If only a subset of the attributes is specified then the selected attributes are called a Projec tion of the Relation The value_part which defines the new values to be inserted into the Relation may take one of two forms E VALUES value list subquery In the first form the value list contains the entry to be inserted into the Relation The value_list must be entered in the order of the attributes as defined in the proj 1ist The Numeric Type of each value must match the attribute type exactly Attributes of type CHAR must be enclosed in apostrophes The following exam
94. her of them This union is performed with the command SELECT UNION OF rel name 1 AND rel name 2 AS rel name 3 Example 4 30 Find the union of Relations Q4STR 1 and Q4STR 2 eSh SELECT UNION OF Q4STR 1 AND Q4STR 2 00000 6 00000 6 00000 4 00000 7 0 00000 3 00000 6 00000 7 00000 3 00000 6 00000 6 00000 4 00000 7 0 00000 4 00000 6 00000 6 00000 4 6 Entries Selected RETRIEVING DATA FROM RELATIONS eShell 057 Users Manual Finally the difference of two Relations is the set of all entries in rel name 1 that are not in re1 name 2 The command to perform this operation is SELECT DIFFERENCE OF rel name 1 AND rel name 2 AS rel name 3 Example 4 31 Find the difference of Relations Q4STR 1 and OASTR 2 eSh SELECT DIFF OF Q4STR 1 AND Q4STR 2 1 00000E 6 2 00000E 6 4 00000E 4 3 5 00000 7 0 0 1 00000 4 2 Entries Selected The important point to remember is that these operations function only for two Relations having the same schemata RETRIEVING DATA FROM RELATIONS 4 19 User s Manual eShell This page is intentionally blank 4 20 RETRIEVING DATA FROM RELATIONS eShell Users Manual 5 GRAPHING RETRIEVED DATA 057 You should familiarize yourself with retrieving data from Relations as described in Chapter 4 prior to using the features described in this Chapter This Chapter describes the commands used to create gr
95. ied with the command SET REPORT TO It is the enabled or disabled with the command ON R REPORT Gun This file may be printed in the normal manner by using the appropriate operating system request after the eShell session is completed As in the case of the other files only one Report File may be opened The request for a new file will result in the previous one being closed There are often times when you may wish to extract data from the eBase database that will be further processed by some other software An Inter face File is provided to support this need This file is defined with the command SET INTERFACE TO file name As in the case of Report and Archive Files the interface file may be enabled and disabled with the command ON INTERFACE When the Interface File is enabled all eQL results will be written to the file in a user defined format A format is defined by the command INTERFACE FORMAT format specifier where the format specifier is a Fortran FORMAT statement en closed in apostrophes Fortran rules are in effect including the need to indicate apostrophes or tics within the format by two consecutive tics Example 11 2 Create a text file containing the grid point identification numbers and coordinates in the indicated format SET INTERFACE TO MYINPUT DAT INTERFACE FORMAT 1X GID I5 3E15 5 SELECT GID X Y Z FROM GRID INTERFACE OFF
96. in You must therefore make certain that any operations between Relations are valid This process is defined more formally by the JOIN operation which is performed with a query as shown in the next example Suppose that you want to know the material property identification number MID of QUAD4 element number 1 The QUAD4 Relation does not contain the MID but the PSHELL Relation does This is similar to the pointer con cept familiar to those using finite element analysis systems By in spection it is seen that EID 1 has a PID of 1 and that from the PSHELL Relation PID of 1 has an MID of 101 This is the answer that is desired RETRIEVING DATA FROM RELATIONS eShell Users Manual Example 4 12 Find the element identification number EID and prop erty identification number PID for element 1 from the QUAD4 Relation and determine the material property identification number MID of the element from Rela tion PSHELL eSh gt SELECT EID QUAD4 PID MID 2 gt FROM QUAD4 MODEL PSHELL WHERE EID 1 AND QUAD4 PID PSHELL PID 1 Entry Selected The syntax of the SELECT command is different from that seen earlier The first difference occurs in the attrib list being selected The sec ond attribute QUAD4 PID has different form It indicates that the PID attribute should be taken from the Relation QUAD4 The general form for the attrib listisnow modified to allow this The list is comprised of attrib terms whic
97. inds of Command Parts including Key words Metasymbols and other special symbols which will help you understand eQL The eQL termination symbol is the semicolon Other Command Parts are discussed in the following sections A Keyword is a Command Part which you must enter exactly as shown in this manual Keywords appear in BOLDFACE typewritten style Abbreviating Keywords For convenience you may abbreviate many of the eQL Keywords This is indicated in the manual by underlining the required part of the Key word as SELECT Simple Metasymbols A Metasymbol is a special Command Part that indicates you must enter a requested data value These symbols are shown in italics A precise definition of each Metasymbol appears at the time it is introduced in the manual For example a command that you will learn later shows both Keywords and a Metasymbol SET SCRIPT TO file name Optional Command Parts INTRODUCTION An optional Command Part whether a Keyword or a Metasymbol is indicated by enclosure in square brackets For example COMMAND NAME user list KEYWORD indicates that the Keyword KEYWORD in the command is optional 1 7 Users Manual eShell Command Part Selectors A Selector defines a group of Command Parts one or more of which must be selected Selectors are enclosed in curley braces LEFT justification CENTER RIGHT Naturally Selectors may also be optional in which case they are encl
98. ine numbers are given the entire active command is listed 1 13 User s Manual 1 14 eShell and if only 1ine 1 is given the single line is listed The active command is positioned to the single line most recently LISTed This position is called the Current Position You may delete lines in an analogous man ner DELETE line 1 TO line n However when the DELETE has no optional line number specified only the line at the current position is deleted A new line may be added to the active command with ENTER new line where the new line is inserted immediately after the current position Note that if the quotation mark is part of new_line it is represented as two consecutive quotation marks You may also edit part of the line at the current position To move to the portion of the active command that you will change you use the LIST command The change is then made with the command CHANGE string_l string_2 where the first occurrence of string 1 is replaced by string 2 Al though the sharp 4 character is shown in the command nearly any delimiter may be used as long as it does not appear in either target string Exceptions are V and Note that embedded blanks are significant and they may appear between the delimiters Example 1 4 List the previous command and change Y to Z eSh LIST 1 TO 3 1 SELECT FROM GRID 2 WHERE X 3 0 3 AND Y 2 0 eSh CHANGE Y Z 3 AND Z 2 0
99. into subsets A simple example is the case in which an EMPLOYEE Relation contains many attributes describing each employee One attribute might be COMMIS SION EARNED Clearly this applies only to sales people who qualify for commission earnings Therefore this field is typically NULL for other classes of employees An eBase Relation may contain NULL fields when only a subset of data has been inserted into the entity as described in Chapter 8 This occurs when insertions are performed using a projection that does not include all of the attributes of the Relation There are certain eQL operations that can internally create such fields If you ever see the word NULL appear in a display it is because an operation has created such a field It is possible to update entries which contain a NULL field New matrices can also be created on the eBase database This is done by using the command CREATE MATRIX mat name mat attrib LIKE old mat where the mat name is the name of the Matrix entity A Matrix is fur ther defined by its characteristics which indude its Storage Mode the Numeric Type of the data that it contains its general Shape and its Static Dimension The Static Dimension specifies the maximum number of Rows or Columns This implicitly defines the Orientation of the entity 3 3 User s Manual CREATE MATRIX mat name 3 4 mat_attr list LIKE old mat E eShell These chara
100. is true for the mixed type Because of these limitations the use of non schematic Freeform entities is discouraged for other than tem porary data RECORD22 Valuecl 4 cum Value 10 RECORD 4 gt Value d Value 1002 Stream Entities A Stream Entity shown in Figure 1 7 is a continuous Stream of Data Values each of which has a Position within the Entity Each Data Value may be directly and randomly addressed by reference to its Position You may best think of this type of Entity as a low level Unix file structure A Stream Entity also has a very simple schema with a single Schema Component it may con Figure 1 7 STREAM Entity ain mixed data types in which case the limita tions described for non schematic Freeform Enti ties also apply or it may contain a single numeric data type or Schematic Stream in which case it has good portability characteristics The length of a Stream Entity is determined by the last Position into which you insert data VavXue l 33 Value 47 Value 93 1 6 INTRODUCTION eShell SYNTAX OF COMMANDS Users Manual Later Chapters of this manual present the precise syntax of the various eQL commands This section introduces the nomenclature used in the command descriptions What is a Command Keywords A command is a sequence of Command Parts which ends with a termina tor symbol There are different k
101. ities The meth ods for doing this are described in this Chapter MATRIX ENTITIES This section describes the commands that you may use to retrieve data from Matrix entities These commands are similar in nature to those available for querying Relations and allow the display of Matrix data in two different forms The MATRIX Select Command Data can be selected from Matrices in a manner similar to that used for Relations The general form of the Matrix query command is MATRIX SELECT format select list FROM mat name WHERE part RETRIEVING DATA FROM NON RELATIONAL ENTITIES 7 1 User s Manual MATRIX SELECT format MATRIX SELECT format select list FROM mat name 7 2 select list FROM mat name WHERE part WHERE part eShell The retrieval of the Matrix data depends on the Orientation of the Ma trix For Column major Matrices columns are retrieved and for Row major Matrices rows are retrieved The format defines the display option that will be used The display options are summarized in Table 7 1 format gt If the display format is omitted and the Storage Mode of the Matrix is COMPRESSED then the BANDED option is used For the UNCOMPRESSED Storage Mode only the FULL option is used The se1ect list allows you to select only some of the COLUMNs or ROWs of the entity term list select list Where the term list isa list of column or
102. l loads LOADS which are stored in SOLVE Note that there may be many other uses and interpretations of these levels which are limited only by your imagination Each directory or subdirectory may contain one or more actual database Entities These are naturally defined by their name However eBase allows another flexibility in that you may have several Entities which have the same basic name but a different subscript number This is use ful if you have for example several sets of analysis results that you are going to correlate There may be several Entities named RESULTS with different indices that contain answers for different problem conditions The concept of subscripts is very powerful You can for example imple ment the version concept found on some computers by simply incre menting your subscript each time you change the data in an Entity Or you can simply create whole arrays of database Entities directly with their subscripts This provides you with the capability to do anything that you like to better organize access and manipulate your data THE MULTISCHEMATIC MODEL ENTITY CLASSES 1 4 As introduced earlier eBase is a collection of data which is organized into Entities An Entity is simply a group of related data that is stored together Unlike purely relational databases which store tables of data eBase has four different data structures which are treated in a unified manner This type of database is ca
103. les which contain the eQL commands used in the manual The following brief description of the Entities on the database will provide you with a physical interpretation of the data There are four directories in the database The first is GEOM the second is MODEL the third is RESULT and the fourth is PLOT The Entities themselves are O GEOM GRID is a Relational Entity that contains for each grid point in a finite element model the identification number GID a coordi nate system identification number CID and the three spatial coor dinates X Y Z assumed to be in some common coordinate system O GEOM QUADA is a Relational Entity that contains finite element defi nitions for quadrilateral plate elements This data includes the ele ment identification number EID the element property identification number PID and the four grid point identification numbers defining the element G1 G2 G3 G4 O MODEL PSHELL is a Relational Entity containing element property data which is referenced by the PID in the QUADA Relation It con tains the PID a material property identification number MID and the thickness T of each element referencing the property 4 RESULT Q4STR 1 and RESULT Q4STR 2 are Relational Enti ties containing three output stress values SIGX SIGY TAUXY repre senting Normal X stress Normal Y stress and shear stress respectively for each element EID The two subscrip
104. lled Multischematic The four eBase Entity classes are O Relational Entities Matrix Entities m Freeform Entities m Stream Entities Each of these Entity classes is briefly described in the following sections INTRODUCTION eShell Users Manual Relational Entities You may view a Relation as simply a table of data eBase tables have rows which are called Entries and columns which are called Attributes A particular data value at a given entry and at Figure 1 4 RELATIONal Entity tribute location is called a Field Figure 1 4 illus trates a typical Relation The attributes of the Re lation are called ATT1 ATT2 ATT3 and ATT4 ATTRIBUTES Note that there are four entries for which this atti ATT2 ATT3 4 data has been defined These attributes taken to ENTRY 13 101 0 0 0 0 0 0 gether with the characteristics of the data which 2 gt 185 0 0 n they contain form the Schema of the Relation L 1 8 m The attribute characteristics or Schema Compo piso nents of a Relation are defined when it is cre ENTRY n gt 104 0 0 1 0 0 0 ated These characteristics include the attribute FIELD name data type and in some cases length are described in detail in Chapter 3 Matrix Entities Matrices form the second Entity class in an eBase database Matrices are arrays of numbers used in mathematical formulae typically encountered
105. m entity to be displayed A 8 eQL COMMAND SUMMARY eShell Users Manual Chapter 8 Inserting Data into Entities This Chapter describes the eQL commands which are available to insert new data into Relational and Matrix entities INSERT INTO RELATION rel name proj list value part Inserts a new entry into the named Relation vdd VALUES value list subquery Specifies the values defining the new Relational entry INSERT INTO MATRIX mat name new value list Inserts a new column or row into the specified matrix row id new value term gt VALUES AT col id value list Specifies the numeric values to be entered into the new matrix column or row These are expressed in the special string format INSERT INTO FREEFORM free name VALUES value list Creates a new Freeform entity Record INSERT INTO STREAM stream name VALUES value list Specifies the Data Values to be appended onto a Stream entity Chapter 9 Updating Data eQL COMMAND SUMMARY This Chapter describes commands which allow individual data entries in both Relations and matrices to be updated UPDATE RELATION rel name SET value list WHERE part Updates or modifies all or part of the data in a Relational entity that meets the specified selection criteria UPDATE MATRIX matrix name value list ROW MERI COLUMN rorc id Updates or modifies all or part of the data in a Matrix column or row
106. mands entered during an eShell interactive session Specifically it is a copy of commands that have executed successfully If a command has been edited only the final form of the command is archived Those which contained user errors are not put on the archive file The principal purpose of this file is to use it during a subsequent eShell session as a script file To define an Archive File the command SET ARCHIVE TO file name is used The Archive File can be enabled or disabled with the command ON ARCHIVE While enabled ON all successful eQL commands are routed to the Ar chive File When disabled OFF commands are no longer written As in the case of the Script File only one archive file may be open If a new SET ARCHIVE request is made then the currently active file is closed and the new one is opened Note that if the command SET SCRIPT is entered interactively then it will not be written to the Archive File On the other hand you may enter the SCRIPT OFF command while the Archive File is enabled This allows the termination of the sequence of eQL commands FILE ENVIRONMENT COMMANDS eShell THE REPORT FILE THE INTERFACE FILE Users Manual previously archived and facilitates the use of the archive file as a Script File in a subsequent eShell session The purpose of the Report File is to contain all query and report output for which you wish to obtain a permanent record The Report File is specif
107. name 1 alt 1 rel name 2 alt 2 where alt 1 is a Basic Name that is used to reference the specified rel name 1 everywhere within the query For example the query of Example 4 13 can be written as eSh SELECT EID A PID MID FROM 2 QUAD4 A MODEL PSHELL WHERE 3 gt A PID PSHELL PID where the Relation QUAD4 has been assigned the symbol A The use of alt names in the SELECT_list is useful if the Relations referenced in the FROM_list are specified as fully qualified names For example eSh gt SELECT EID A PID MID FROM 2 gt GEOM QUAD4 A MODEL PSHELL B WHERE 3 A PID B PID A special convention allows you to use the Basic Name of the Relation as the a1t name eSh gt SELECT EID QUAD4 PID MID FROM 2 gt GEOM QUAD4 MODEL PSHELL WHERE 3 gt QUAD4 PID PSHELL PID If several subscripted versions on an entity are involved in a query then it is necessary to use an alt name to differentiate the selected attributes eSh gt SELECT A SIGX B SIGX FROM 2 gt RESULT Q4STR 1 A RESULT Q4STR 2 RETRIEVING DATA FROM RELATIONS eShell Users Manual GROUPING DATA DURING THE SELECTION You may group the results of a query by using the GROUP part in the SELECT command The grouping operation partitions the Relation into a number of subsets based on identical values of one or more attrib utes The GROUP part follows the WHERE part and has the form SELECT select list FROM part WHERE part GROUP
108. o an existing eBase database CREATE RELATION rel name schema list LIKE existing rel name Creates a new Relation with a specified schema on the database Alter nately the schema of an existing Relation may be used to specify the schema CREATE MATRIX mat name matrix attrib LIKE existing mat name Creates a new Matrix entity with specified attributes on the database Optionally the attributes of an existing matrix may be used to specify the schema CREATE FREEFORM ent name num type LIKE existing ent name Creates a new Freeform entity with specified attributes Optionally the attributes of an existing entity may be used to specify the schema eQL COMMAND SUMMARY eShell Users Manual CREATE STREAM ent name num type LIKE existing ent name Creates a new Stream entity with specified attributes Optionally the attributes of an existing entity may be used to specify the schema Chapter 4 Retrieving Data from RELATIONs eQL COMMAND SUMMARY The most powerful use of the eQL language is its ability to retrieve data from an eBase database This Chapter describes the commands that may be used to retrieve data from Relations and also the use of indexing to improve query performance RELATION SELECT select list FROM part WHERE part GROUP part ORDER part Selects all or part of a Relation and displays the result WHERE part WHERE search condition Qualifies
109. of entities and subdirectories within the directory If you select the DATE option which applies to the restric tion Keywords as well the listing includes two dates the date that each entity was created and date when it was last modified DIRECTORIES AND ENTITIES eShell Users Manual The Entity Directory You may also request a directory listing by referencing a fully qualified entity name The DIR command form is then DATE DIRECTORY ent name ALLVER Swan where ent name is a fully qualified entity name The options ALLVER and SUMMARY only used when ent name has subscripted versions The following examples show the directory listing produced by this com mand Example 2 6 Request a directory listing for entity GRID eSh DIR GEOM GRID Relation TESTEB GEOM GRID GRID 10 Entries If ent name has subscripted versions and you enter only the Basic Name of the entity then you obtain the directory list for the Released Version Example 2 7 Request a directory listing for the Released Version of en tity Q4STR eSh gt DIR RESULT Q4STR Relation TESTEB RESULTS Q4STR 2 Q4STR 2 4 Entries By including the ALLVER option you will obtain the directory for each of the subscripted versions of the entity Example 2 8 Request a directory listing for all subscripted versions of entity O4STR eSh gt DIR RESULT Q4STR ALLVER Relation TESTEB RESULT Q4STR Q4STR 1 4 Entries Q4
110. ommand entry NEW TEMP OPEN database name phys name READ params WITH WRITE ADMIN Opens an existing or new database for activity HELP command part list Requests information about eQL commands CLOSE database name DELETE Closes an open database LIST line 1 TO line n List all of or selected lines of the active command DELETE line 1 TO line n Deletes current or selected lines of the active command ENTER new line Adds a new line to or within the active command CHANGE string 1 string 2 Changes the first occurance of a string of characters within the active command RUN Executes the active command END Terminates the eShell session DEFINE symbol name value Defines a substitution symbol symbol name UNDEFINE x Removes the definition of a substiution symbol eQL COMMAND SUMMARY eShell Users Manual SET PASSWORDS ON database name password list Allows you to change passwords on any open database for various data base privileges READ WRITE password ADMIN password term READ CLEAR 4 WRITE ADMIN Defines the new passwords for one or more privilege levels Chapter 2 Creating and Maintaining Directories eQL COMMAND SUMMARY You may structure your database to reflect the organization of your data by using a directory structure This Chapter describes the commands used to create and maintain that structure MKDIR p
111. onal attributes and symbols Addition ally there are special rules for Entity names and host computer files These are described in the following sections Basic Naming Rules A Basic Name must be no longer than 32 characters It must begin with a letter 2 and the remaining characters may be letters 7 digits 0 9 or the special symbols underscore _ and dollar Path Naming Rules INTRODUCTION A Path defines a database and a directory hierarchy The general form of a path is path gt database name dir name list where the database name is the logical name of an open eBase data base and the dir name list is a series of one or more dir names separated by slashes dir name list gt dir name dir name where each dir name is directory name 1 9 User s Manual eShell Entity Naming Rules An eBase Entity is described by an optional Path a Basic Name and an optional subscript list ent name gt path basic name subscript The optional subscript which is enclosed in square brackets 1 has the form subscript gt sub list Each sub term is an integer value The number of sub terms must match the number specified when the first subscripted version of ent name was created VALID ENTITY NAMES ILLEGAL ENTITY NAMES ELEMDATA COORDQX Illegal character Grid Coordinates 1LOAD Starts with number KAA 1 101 KAA 2 Wrong number of
112. onstants and functions Such expressions can be used as selections which may be plotted When this is done the selection is called a Virtual Attribute because it only exists as the result of the query of the rules for arithmetic expression evalu ation follow the standard rules of Fortran Example 5 10 Create a graph with two curves using data from Relation TRANS The first is 100 times the z dispacement attribute Z and the second is the z velocity attribute W Label the plot accordingly CD PLOT SET XTITLE TO Z 100 SET YTITLE TO Z Velocity SET FTITLE TO Wing Transient Response XYPLOT 100 Z W FROM TRANS The resulting graph is shown below Wing Transient Response 1200 1000 800 NS 200 7 400 C LDL Z Velocity N EC 800 600 400 200 0 200 400 600 800 Z Disp 100 The ADDCURVES Command There may be cases in which you would like to add additional curves to a plot that you have already created You may do this with the command ADDCURVES x attrib y attrib list FROM part WHERE part GROUP part ORDER part As with the XYPLOT command the x attrib y attrib list and FROM part are required And again as with all queries the WHERE part GROUP part and ORDER part are each optional but when any or all of them appear in
113. or places constraints on the entries of the Relation being se lected The WHERE part may also specify one or more subqueries GROUP part GROUP BY attribute list Requests that the resulting data be grouped by unique values of the selected attributes ORDER part ORDER BY sort list Requests that the results of the query be sorted on one or more selected attributes SELECT INTERSECTION OF rel name 1 AND rel name 2 AS rel name 3 Selects the set of entries contained in both of two Relations which have the same schema and optionally creates a new Relation containing these entries SELECT UNION OF rel name 1 AND rel name 2 AS rel name 3 Selects the set of distinct entries contained in either of two Relations which have the same schema and optionally creates a new Relation con taining these entries A 5 User s Manual eShell SELECT DIFFERENCE OF rel name 1 AND rel name 2 AS rel name 3 Selects the set of entries in one Relation that are not in another Both Relations must have the same schema and optionally creates a new Rela tion containing these entries Chapter 5 Graphing Retrieved Data A 6 This Chapter describes the commands that may be used to graph or plot retrieved data from Relations and control the windows where the plots are displayed SET ACTIVE WINDOW TO plot win id Selects an active plot window PLOT WINDOW plot win id CLEAR ALL PLOT WINDOWS Removes all or a speci
114. or sort the results of a query by using the OR DER part in the SELECT command The sorting operation may be per formed on one or more of the attributes which appear in the select list When present the ORDER part appears last in the query The form of this clause is ORDER part ORDER BY sort list where the sort_list isa list of one or more sort terms separated by commas which have the form sort_term gt 1 1 DESCENDING attribute name ASCENDING where each attribute name must appear in the select list The alternate form ordinal allows the attribute to be specified as an integer value which corresponds to the order of the appearance of the attribute in the select list Either form may be used interchangeably some attributes may be named while others are selected by their Ordinal It is required that Virtual Attributes be referenced by their Ordinal sort ing is performed in ascending order ASCENDING unless the optional keyword DESCENDING is present for a particular attribute in which case the sort is in descending order Sorting is performed in the sequence specified in the ORDER part Example 4 16 Query the Relation Q4STR 1 and order the results on SIGX and SIGY eSh SELECT FROM RESULT Q4STR 1 2 gt ORDER BY SIGX SIGY 00000 06 00000 06 00000 04 00000 06 00000 06 00000 04 00000 06 3 00000 06 00000 04 00000 06 1 00000 07 00000 03 4 Entries Selected
115. ory called the Root Directory which is denoted symbolically by a slash character You may create a new directory using the command MKDIR path where the path ends with the directory name which will be created Often directories other than the root directory are called Subdirectories Example 2 1 Create the directory ANALYSIS and a subdirectory called FEA on the TESTEB database eSh MKDIR ANALYSIS eSh MKDIR ANALYSIS FEA THE WORKING DIRECTORY When you open an eBase database you are be placed in the Root Direc tory of the database that you OPEN Your location is called the Working Directory Each time you open another database your working directory becomes the Root Directory of that database To move to another direc tory you use the command CD path where path specifies the directory name to which you will move If no pathis specified then eShell identifies your current Working Directory Example 2 2 Move to the directory ANALYSIS FEA CD ANALYSIS FEA Or CD ANALYSIS CD FEA CD Working Directory TESTEB ANALYSIS FEA DIRECTORIES AND ENTITIES eShell Users Manual REMOVING DIRECTORIES 057 LISTING DIRECTORIES You may remove an existing directory using the command RMDIR path where the path ends with the directory name which will be removed Example 2 3 While in the Root Directory remove the directories FEA and ANALYSIS from the TESTEB data
116. ory on the TESTEB database DIR GEOM Directory TESTEB GEOM Class Size E REL 10 Entries QUADA REL 4 Entries Directory Contains 2 Entities DIR RESULT Directory TESTEB RESULT Class Size Entries Subscript Versions RelVer 2 Directory Contains 2 Entities DIR MODEL Directory TESTEB MODEL Class Size PSHELL Entries TESTFREE FRE Records STRM STR Values GG MAT Columns Directory Contains 3 Entities The listing shows the name of each entity its class and a description Subscripted entities are indicated by an asterisk which follows the class The description depends on the entity class For Relations it is the number of entries O For Matrix entities it is the number or columns or rows depending on the storage mode For Stream entities it is the number of Data Values and For Freeform entities it is the number of records For all classes of subscripted entities it is the number of subscripts used the number of versions which exist and the subscript of the Released Version if any A discussion of Released Versions is found later in this Chapter You may limit the directory listing by using one of the options shown in the command For example to restrict the listing to a single entity class or to the subdirectories within the directory you use the corresponding Keyword The SUMMARY option simply lists the last line of the listing which gives a count of the number
117. osed in brackets Metasymbol Suffixes Many commands allow lists of user input In these cases the command description uses the suffix list to indicate this Each term in the list is suffixed with aterm Unless otherwise specified the terms in a list are separated by commas user list gt user term user term Throughout the manual you will find commands which include list Me tasymbols If the list has the form shown above then only the terms will be defined Complex Metasymbols SELECT attr name list FROM rel name list 1 8 WHERE clause For a complex command there may be one or more Command Parts which are themselves composed of many Command Parts In such cases each complex Command Part is discussed separately and the relationship of the Command Part to the whole command is shown in the left margin while the exact definition appears in the body of the text adjacent to it WHERE clause gt Note that the Metasymbol is highlighed in boldface italics INTRODUCTION eShell Users Manual Important Information Two other conventions are used to assist your learning of eShell These are callouts which provide important information or give you reminders useful when performing the tutorial examples Ue This is important information v This is a reminder NAMING eBase OBJECTS Many objects within the eBase database are given names These include directories Entities views Relati
118. ot that you create will destroy the plot that previously occupied that window Once you have set the current plot window it will be used for all sub sequent plots that you create until you redefine it explicitly or clear it using the command PLOT WINDOW plot win id CLEAR ALL PLOT WINDOWS If you CLEAR all of the plot windows the active window is reset to one As noted above you may replot the data is a plot window with the command REPLOT plot win id If you do not specify a plot win id then the data in the current active window are REPLOTted THE PLOTTING COMMANDS Data retrieval and plot creation are accomplished with the 2 D plotting commands XYPLOT ADDCURVES and MXYPLOT These are described in the following sections THE XYPLOT COMMAND Data retrieval and graph creation is accomplished with a single XYPLOT command The general form of this command is XYPLOT x attrib y attrib list FROM part WHERE part GROUP part ORDER part The x attrib y attrib list and FROM part are required As with all queries the WHERE part GROUP part and ORDER part are each optional but when any or all of them appear in the XYPLOT com mand they must appear in the order indicated The richness of this com mand requires numerous examples 5 2 GRAPHING RETRIEVED DATA eShell Users Manual The simplest form of the command is XYPLOT x attrib y attrib list FROM rel name where x attrib and the y attrib list a
119. otection of database contents from inadvertent distruc tion Interface File An external host computer file that contains the results of eBase queries which have been formatted in a manner which facilitates their further processing by some other software GLOSSARY eShell GLOSSARY Users Manual Key Asingle unique Index for a Relational entity is often called a Key Keywords Character string within eQL commands that must be entered exactly as shown in this manual Matrix Entity Arrays of numbers used in mathematical formulae typi cally encountered in engineering and physical science software applica tions A matrix is defined in the standard mathematical manner as an array of n rows and m columns See also Compressed Storage Mode Multischematic Database A database which allows different types of data structures to be represented in an efficient manner See also Entity Classes Null Field Is a field within a Relational entity which is undefined This occurs for example when a new entry is inserted into the entity where all of the attributes are not assigned values Orientation Matrix Defines the manner in which a Matrix entity is stored Selections Column major storage and Row major storage respec tively See also Compressed Uncompressed Column major and Row major Passwords eBase databases have three levels of Passwords which can be used to secure the data against inadvertent destruction or unauthorized
120. part GROUP BY attribute list GROUP part ORDER part where the attribute listisalist of one or more attribute names The grouping on floating point attributes RSP RDP CSP or RDP is not ie allowed because even though a TOLERANCE may be specified the partitioning is ambiguous Example 4 14 Query the Relation QUAD4 and group the results on the property identification number PID eSh gt SELECT PID FROM QUAD4 2 gt GROUP BY PID 2 Entries Selected The grouping of the results of a query is especially useful when group operations are performed on the results Example 4 15 Find the maximum Normal X stress for each property identification number used for QUAD4 elements eSh gt SELECT QUAD4 PID Q4STR SIGX 2 gt FROM QUAD4 RESULT Q4STR 1 WHERE QUAD4 EID Q4STR EID GROUP BY QUAD4 PID MAX SIGX 2 00000 06 3 00000 06 2 Entries Selected Notice that a join condition described in more detail later in this Chapter was required to attach the common attribute EID between the Relations QUAD4 and Q4STR 1 The maximum stress was then extracted from each of the groups Also note that the Q4STR 1 relation was fully quali fied since in was not in the Current Working Directory RETRIEVING DATA FROM RELATIONS 4 11 User s Manual eShell SORTING DATA DURING THE SELECTION SELECT select list FROM part 4 12 WHERE part GROUP part ORDER part You may also order
121. perators in a query 4 15 4 16 grouping query results 4 11 Inserting into a projection 8 2 Inserting new data 8 2 Inserting with a subquery 8 2 Intersecting two Relations 4 18 Joining two relations 4 9 Mixing attributes and group operators 4 17 Multiple subqueries 4 14 Nested subqueries 4 15 NULL fields when altering 9 7 Plotting a relation 5 3 Query with an array attribute 4 3 Querying a relation 4 2 Querying with a Path 4 4 Selecting DISTINCT attributes 4 3 Simple subquery 4 13 sorting query results 4 12 Subquery resulting in a set 4 14 Index 3 User s Manual The COUNT group operator 4 17 Union of two Relations 4 18 Updating 9 2 Updating with a subquery 9 3 Updating with a WHERE clause 9 2 Using WHERE ina query 4 4 4 5 Using WHERE in an XY plot 5 8 5 9 WHERE clause with set selection 4 6 WHERE with logical expression 4 5 XY plot with logical expression 5 9 XY plotting with a Path 5 7 Examples Report Column formats 12 4 Column labels 12 3 Titling 12 4 Using BREAK ON 12 5 Examples Stream Inserting data values 8 5 Printing 7 7 Updating 9 5 EXPORT eOL command 11 5 Exporting databases 1 17 11 4 Field 1 5 File environment Archive file 11 2 Exportfile 11 4 Importfile 11 4 Interface file 11 3 Reportfile 11 3 Scriptfile 11 1 Floating point values Comparison TOLERANCE 4 4 5 9 13 2 Formats Current environment 13 3 Defaults for numeric 12 6 EXPORT and IMPORT files 11 5 Interface file 11 3 R
122. ple illustrates the use of this form of the INSERT command INSERTING DATA INTO ENTITIES 8 1 User s Manual 8 2 eShell Example 8 1 Move to Directory TUTOR make a copy of the GRID Rela tion called INS GRID and insert a new grid point 15 11 CID 0 and X Y 2 2 5 0 0 0 0 0 into it eSh CD TUTOR eSh COPY GEOM GRID TO INS GRID eSh INSERT INTO INS GRID VALUES 11 0 5 0 0 0 0 0 1 Entry Inserted If you specify a Projection then all attributes which are not specified in the proj list are given a Null value in the new entry If any of the attributes not in the Projection have been defined to be NOT NULL then you may not INSERT into the Relation Example 8 2 Insert a new grid point ID 12 and with X 10 0 into the INS GRID Relation and verify the result eSh INSERT INTO INS GRID GID X 2 VALUES 12 10 0 1 Entry Inserted eSh SELECT FROM INS GRID WHERE GID 12 The second form of the value part is a subquery By using the subquery selected portions of one Relation may be inserted into an other as shown in the next example Example 8 3 Create a new Relation called GRIDY1 This Relation has the same schema as GRID Insert all grid points from INS GRID with Y coordinates of 1 0 into the new Rela tion CREATE RELATION GRIDY1 LIKE INS GRID Relation TESTEB TUTOR GRIDY1 Created INSERT INTO GRIDY1 SELECT FROM INS_GRID WHERE Y 1 0 5 Entries Inserted Note that the attribu
123. query of example 12 3 placing appropriate titles on the output report SET HEADER TO GRID POINTS ALONG STATION X 4 0 PAGE SET FOOTER TO TESTEB SAMPLE CENTER DATE SELECT FROM GRID WHERE X 4 0 GRID POINTS ALONG STATION X 4 0 4 00000 1 00000 0 00000E 00 4 00000 0 0 0 00000E 00 TESTEB SAMPLE 2 Entries Selected REPORT GENERATION eShell Users Manual GROUPING COMMANDS eQL provides a special command that allows the legibility of reports to be enhanced by spacing between related groups of data This command 15 SET BREAK ON attribute name SKIP PAGE where the attribute name is one which appears in the next query command The optional SKIP parameter requests that lines be skipped when a new value of attribute name is encountered PAGE requests that the report begin a new page when the attribute name changes value Note that the SET BREAK ON command must be made prior to a query that contains any GROUP part or SORT part that references the same attribute name Example 12 5 Query the QUAD4 Relation selecting all attributes sort ing them by the property identification number PID and skipping a line between each property type eSh SET BREAK ON PID SKIP 1 eSh SELECT FROM QUAD4 SORT BY PID 4 Entries Selected PAGE CONTROL COMMANDS Certain page control information may be controlled with eQL com mands This information allows different print characteristics to be de fined The fir
124. re respectively a single attribute and a list of one or more attribute names separated by commas that are contained in the Relation specified by rei name The x at trib defines the x axis of the graph and the y attrib list define the y axis data that will be plotted Each attribute in the list results in a separate curve on a single plot The maximum number of curves that may appear on a single plot is nine lt p Therefore the number of elements specified in the y list may not exceed nine Example 5 1 Create a plot of displacement component T3 versus time step TIME from Relation THISTORY eSh CD PLOT eSh XYPLOT TIME T3 FROM THISTORY which results in the graph HUM d HL TEL T An example which shows multiple curves is illustrated next Example 5 2 Create a plot using Relation THISTORY of the two real displacement components T1 and T3 versus the time step TIME eSh XYPLOT TIME T1 T3 FROM THISTORY This results in the plot GRAPHING RETRIEVED DATA 5 3 User s Manual eShell s 0 8 t d f M i h i al DL tlg t pc gt AIAMAA AU M ULMIM MM Tu t L La Po ad oa 4 js it LE Y TOY THE GRAPH EL
125. ributes Numerictype 3 3 Shape 3 3 Static dimension 3 3 Storage mode 3 3 Matrix entities 1 5 Attributes of 3 4 Creating 3 3 Directory entry 2 4 Inserting columns or rows 8 3 MATRIX SELECT 7 2 Numeric type 1 5 Print options 7 2 Removing data from 10 3 See also Report generation Restrictions on UPDATE operation 9 4 Shape 1 5 Shape changes 10 3 Storage Mode 1 5 Terms 1 5 Updating 9 4 MATRIX SELECT eQL command 7 1 MAX operator 4 15 Metasymbols 1 7 MIN operator 4 15 MKDIR eQL command 2 2 Multiple databases Working with 1 17 Multischematic database Description of 1 2 MXYPLOT eQL command 5 13 N Name component 1 2 Naming rules Basicname 1 9 eBASE objects 1 9 Entities 1 10 Files 1 10 NOT IN option in WHERE clause 4 6 5 10 NULL attributes When altering Relational schema 9 6 NULL fields 3 3 Online manual 1 11 OPEN eQL command 1 2 1 12 Operators Arithmetic 4 4 Logical 4 4 OR function 4 4 Users Manual Orientation Column major 1 5 Row major 1 5 P Page Format Current values 13 3 Password privileges 1 12 1 16 Current values 13 3 Performance query 6 3 Portability 1 17 Position See Stream entities Preference files 1 11 Privilege requirements For altering schema of Relation 9 6 For updating a Matrix 9 4 For updating a Relation 9 3 Inserting columns into a MATRIX 8 3 Inserting data values into a STREAM 8 5 Inserting entries into RELATIONs 8 2 Inserting records into a FREEFORM 8 4 To create
126. rline character then a space will be skipped between the at tributes names and their values Consider the following example 12 3 User s Manual PAGE TITLES 12 4 eShell Example 12 3 Query the Relation GRID for all grid points with X coor dinates of 4 0 Use a format of F9 5 for the X and Y coordinates label the GID field GRID ID and use an equal sign to underline attribute names SET COLUMN GID LABEL GRID ID Permanent Report Column GID Created SET COLUMN X FORMAT F9 5 Permanent Report Column X Created SET COLUMN Y FORMAT F9 5 Permanent Report Column Y Created SET UNDERLINE TO SELECT FROM GRID WHERE X 4 0 4 00000 1 00000 0 00000E 00 4 00000 0 0 0 00000E 00 eQL provides you with commands to place titles at either the top of each page or screen the bottom or both The commands used to do this are SET HEADER TO header line justification DATE PAGE SET FOOTER TO footer line justification DATE PAGE Both header line and footer line may contain blanks Multiple lines are denoted by the slash as in column titles The optional DATE and PAGE parameters request that the date and page number be placed on each page The justification parameters and defaults are the same as for the SET COLUMN command The effects of justification and titling depend upon certain page control information that are discussed later in this Chapter Example 12 4 Recreate the
127. rm of such a variable is amp 1 You may use from one to nine parameters i e amp 1 through amp 9 in a com mand file When you invoke the Script File you then include the actual values of the parameters with the START command as shown in the following example FILE ENVIRONMENT COMMANDS 11 1 User s Manual THE ARCHIVE FILE eShell Example 11 1 Invoke the Script File named VARGRID with parameters 5 0and 2 3 eSh START VARGRID 5 0 2 3 Script Files allow you to save and recall frequently used eQL command sequences For example the developers of eShell used this feature to save test cases which could be rerun as often as necessary Only one Script File may be active at a given instant If the SET SCRIPT command is issued while a Script File is active the active file is sus pended and the new one is opened Control returns to the previous Script File when the current one is exhausted Also note that eQL com mand editing cannot be performed on commands which enter eShell from the Script File because the user is not in control of the terminal You may include variables within the commands in your Script File by using the symbol substitution protocol discussed in Chapter 1 Namely commands may include symbols of the form amp symbol name You may then use the DEFINE command to give these variables a value prior to invoking the Script File An Archive File is a text file that contains an historical record of the com
128. rmance matrix utility subroutines which have been optimized for many different com puters This library includes routines for matrix algebra linear equation solving eigenvalue extraction and others The high level management of engineering data is closely related to the management and performance of the actual product development proc ess Data is created and used within limited well defined domains These include such areas as CAD Modeling Structural Analysis Shock and Vibration Master Dimensions Loads Analysis Propulsion Systems Per formance Requirements and many more Typically data is named and structured in ways which relate to the specific domain When an engi neering task has been successfully completed the data is released by the responsible engineering management This overall process represents a natural hierarchy that results from the decomposition of a complex proc ess into its simpler components Determining the most useful and effi cient method for organizing this information can be called Data Modeling eBase provides powerful tools for data modeling These tools are summarized in this Chapter An eBase database is a collection of Entities An Entity can be viewed as an object with three components as shown in Figure 1 1 The Entity has a Name Component which is used to identify it a Schema which is a set of rules that describes the data contents of the Entity and it has Data Com ponent which is the actual data its
129. row identification numbers depending on the Orientation of the Matrix Only the terms specified in this list will be extracted from the Matrix You may select all values by using the asterisk shorthand notation The Matrix entity that you are querying is specified by mat name Table 7 1 Matrix Print Options OPTION DESCRIPTION FULL Prints all terms in the Matrix Default for UNCOMPRESSed Matrices Prints terms in each column beginning with the first nonzero term BANDED and ending with the last nonzero term Defaultfor COMPRESSed Matrices RETRIEVING DATA FROM NON RELATIONAL ENTITIES eShell Users Manual The following examples illustrate the use of these options Example 7 1 Query the KGG Matrix obtaining a FULL listing eSh MATRIX SELECT FULL FROM KGG lumn Major Compressed Real Double Precision Symmetric 6 Rows 6 Columns Density 52 0 Column 3 0 00000 400 000 00000 0 00000 00000 0 00000 0 00000 0 00000 0 00000 0 00000 1000 00 1100 00 For large sparse Matrices the FULL format can be overburdening A more space efficient option is the BANDED format illustrated in the next example Example 7 2 Query the KGG Matrix obtaining a BANDED listing eSh MATRIX SELECT FROM KGG lumn Major Compressed Real Double Precision Symmetric 6 Rows 6 Columns Density 200 000 700 000 900 000 1000 00 1100 00 RETRIEVING DATA FROM N
130. s See also eQL SET commands ADDCURVES 5 11 ALIAS 2 8 ALTER 9 6 CD 2 2 CHANGE command line 1 14 CLOSE 1 2 1 13 COMPRESS 2 8 COPY 2 8 CREATE FREEFORM 3 5 CREATE INDEX 6 1 CREATE MATRIX 3 3 CREATE RELATION 3 1 CREATE STREAM 3 6 DEFINE 1 15 11 2 DELETE command line 1 14 DELETE FROM FREE 10 4 DELETE FROM MATRIX 10 3 DELETE FROM RELATION 10 2 DESCRIBE 2 6 DIR 1 3 2 3 2 5 END 1 15 ENTER command line 1 14 EXPORT 11 5 FREEFORM SELECT 7 5 HELP 13 2 IMPORT 11 5 INSERT INTO 8 1 INSERT INTO FREEFORM 8 4 INSERT INTO MATRIX 8 3 INSERT INTO STREAM 8 5 INTERFACE 11 3 LIST command line 1 13 MATRIX SELECT 7 1 eShell MKDIR 2 2 MXYPLOT 5 13 OPEN 1 2 1 12 PURGE 1 10 10 1 PURGEINDEX 6 6 RELEASE 2 8 RENAME 2 8 REPLOT 5 2 REPORT 11 3 RMDIR 2 3 RUN command line 1 14 SELECT 4 1 SELECT DIFFERENCE 4 18 SELECT INTERSECTION 4 18 SELECT UNION 4 18 SET ACTIVE WINDOW 5 2 SETARCHIVE 11 2 SETINTERFACE 11 3 SET PASSWORDS 1 16 SET REPORT 11 3 START 1 10 11 1 STREAM SELECT 7 7 TREE 13 1 UNCOMPRESS 2 8 UNDEFINE 1 15 UNRELEASE 2 8 UPDATE 9 1 UPDATE FREEFORM 9 4 UPDATE MATRIX 9 3 UPDATESTREAM 9 5 XYPLOT 5 2 eOL SET commands BREAK 12 5 COLSPACE 12 5 COLUMN 12 2 FLOATWIDTH 12 6 FOOTER 12 4 HEADER 12 4 INTWIDTH 12 6 LINEWIDTH 12 5 PAGELENGTH 12 5 PASSWORD 1 16 UNDERLINE 12 3 eOL Description 1 1 eSHELL Description 1 1 Using the program 1 11 Examples Creation Freeform 3 5 Matrix 3 5 Relation 3 2 Relation with arr
131. st such command is SET LINEWIDTH TO n which defines the width in characters of the display area If not speci fied LINEWIDTH is 80 The command SET PAGELENGTH TO n controls the number of lines in the display area If not specified this value is 24 To control the number of spaces between columns of output the command SET COLSPACE TO n is used The default spacing is two characters REPORT GENERATION 12 5 User s Manual 12 6 eShell The final commands are SET INTWIDTH TO n SET FLOATWIDTH TO n which set the default field width for integer and floating point numeric fields respectively The default value depends on the data type of the attribute I8 for integer values INT 1P E12 5 for floating point values RSP RDP CSP and CDP A FLOATWIDTH cannot be less than 8 characters Character attributes are printed with a field width equal to the length they were defined to have when created For array attributes all ele ments are printed following the rules above These defaults can be modi fied in two ways The first is by the specification of a SET COLUMN command The second is an automatic adjustment by eShell to accommo date column title information In the absence of a SET COLUMN the minimum width printed is that which allows the full title to be displayed This was illustrated in Examples 12 2 and 12 3 Note that any or all page control commands may be listed in a single SET command by li
132. sting them separated by commas REPORT GENERATION eShell Users Manual 13 UTILITY FUNCTIONS DIRECTORY TREE UTLITIES This Chapter describes several utility functions available in eShell that allow the user to control the tolerance on floating point comparisons and provide online HELP information and a summary of current environment variables The Directory structure of your eBase database can be displayed using the command TREE path where path is an optional Path name The directory structure shown recursively descends from the path location Example 13 1 Move to the Root Directory and display the Directory tree for TESTEB i4 MODEL GEOM RESULTS 13 1 User s Manual eShell TOLERANCE FOR FLOATING POINT COMPARISONS ONLINE HELP 13 2 The eBase numeric data types RSP RDP CSP and CDP are approximate in nature so that it is possible for computed values that are in fact identi cal to differ in the least significant decimal places Because eQL allows comparisons of these numbers it is usually necessary to define a compari son tolerance called 8 Let A be an attribute in a relation with a particular value a and let p be an approximate numeric value specified by the user in a query Then the relational operators are modified as o p if and only if p 6 lt a lt p a p if and only if p 6 gt o or a gt p o gt p if and only if a gt p a gt p if and only if a
133. string multi line title Defines column heading label as one or more lines LEFT justification RIGHT CENTER Selects column titling justification option Iw Fw d Ew d Dw d Aw Gw d format info FORMAT Specifies the exact format to be used in displaying a column SET UNDERLINE TO underline character Sets the default character used for underlining attribute names in the output display SET HEADER TO header line justification DATE PAGE Defines text information to be placed at the top of each page of a display SET FOOTER TO header line justification DATE PAGE Defines text information to be placed at the bottom of each page of a display SET BREAK ON attribute name SKIP n PAGE Selects vertical spacing options as a function of changes in one or more attribute values SET LINEWIDTH TO n SET PAGELENGTH TO n SET COLSPACE TO n SET INTWIDTH TO n SET FLOATWIDTH TO n Selects characteristics of the the output display including the width of an output line the number of lines in a display the number of spaces be eQL COMMAND SUMMARY eShell Users Manual tween displayed attributes the width for displaying integer values and the width for displaying floating point values Chapter 13 Utility Functions eQL COMMAND SUMMARY This Chapter describes several utility functions available in eShell TREE path Displays the Directory structure of an
134. sum mary of the current report page settings VERSION displays the current version number of the eShell program CONFIG shows the Configuration parameters which are in effect and OPEN DATABASES gives the name status and access level of all open databases 13 3 User s Manual eShell This page is intentionally blank 13 4 UTLITIES eShell Users Manual A eQL COMMAND SUMMARY eQL COMMAND SUMMARY This Chapter provides a summary of all eQL commands and a general description of their function All of the commands have been described in detail in previous Chapters of this manual The eQL functions are grouped into the following categories OMOodoOd OOO OOO oO oO Oo Oo Using eShell and eQL Command Editing Directory Creation and Maintenance Entity Creation Data Retrieva Relations Graphing Retrieved Data Indexing Relational Entities Data Retrieval Non Relational Entities Inserting Data into Entities Updating Data Removing Entities and Data File Environment Commands Report Generation Commands Utility Commands Many of the eQL commands use common parts or clauses each of which may be very complex These clauses called metasymbols are also in cluded in this Appendix Users Manual Chapter 1 Using eShell A 2 eShell This Chapter describes how you use the eShell program This includes the commands to open and close databases how to enter commands and how to use symbols to assist in your c
135. t UPDATE NEW GRID SET Y Y 1 0 WHERE X 2 0 AND Y 1 0 1 Entry Updated UPDATING ENTITY DATA eShell Users Manual Finally subqueries may be used in the UPDATE command to determine the range of entries to be updated as shown in the next example Example 9 4 Change the property identification number of all NEW QUADA4 elements having normal y stresses greater than 2 0 6 in Subcase 1 to PID 3 UPDATE NEW_QUAD4 SET PID 3 WHERE EID IN SELECT EID FROM RESULT Q4STR 1 WHERE SIGY gt 2 0E 6 2 Entries Updated SELECT EID PID FROM NEW 4 WHERE PID 3 2 Entries Selected In order to UPDATE a Relation it is necessary to have the WRITE privilege for the database UPDATING MATRIX ENTITIES UPDATE MATRIX mat name SET rorc id TO value list UPDATING ENTITY DATA It is also possible to selectively update columns or rows of Matrix entities subject to specific restrictions To do this the command UPDATE MATRIX matrix name value list ROW n COLUMN ror uid is used The matrix_name must be the name of an existing Matrix entity The new data values are given in the value_list which is composed of a list ofvalue_terms value_term gt SET VALUES AT TERM corr_id TO values The corr_id is an integer value indicating the starting column or row position of the numbers found in the list of values Special rules de scribed in the next section must be obeyed when specifying the corr_id
136. te names and Numeric Types are those defined in Chapter 1 The INSERT command requires the WRITE privilege INSERTING DATA INTO ENTITIES eShell Users Manual ADDING NEW COLUMNS OR ROWS TO MATRICES INSERT INTO MATRIX mat name new value list An additional feature of eQL is the capability to insert new columns or rows into existing Matrix entities The new column or row is actually appended to the current entity That is the column or row number inserted is one greater than the last one currently in the Matrix Y ou insert columns into a Column major Matrix and rows into a Row ma jor Matrix In both cases the command to perform this operation is INSERT INTO MATRIX matrix name new value list The new value list is composed of one or more terms of the form row id new value term VALUES AT col id value list where the new column or row is entered a series of nonzero terms value list within the new column or row This is done by specifying the first nonzero row idor col idand following it with the list of data values The values are assumed to occupy successive row positions beginning with row id or successive column positions beginning with col id The value list is a list of Matrix terms whose Numeric Types are conformable to those defined in the entity schema Example 8 4 In Directory TUTOR make a copy of Matrix entity KGG named INS KGG and add a seventh column to it Recall that KGG is stored in the
137. ted by the next example Example 1 5 Define the symbol X and use the symbols X and Y to per form the query shown DEFINE X 3 0 SELECT FROM GRID WHERE X amp X AND Y amp Y ENTER VALUE FOR SYMBOL Y 2 0 Once a symbol is defined either explicitly or through a prompt it retains its value until you remove the symbol using the command symbol name UNDEFINE The asterisk may be used to UNDEFINE all previous definitions Sev eral other conventions may be used for symbol definition If you want a symbol to be concatenated with additional characters then you follow the substitution with a period and the additional characters For instance eSh DEFINE FOO XYZ eSh SEL FROM amp FOO 01 results in User s Manual eShell eSh SEL FROM XYZ01 Finally if it is necessary to include a period in the string immediately following a symbol then you must specify two periods eSh DEFINE BAR ABC eSh SEL amp BAR GID FROM amp BAR results in eSh SEL ABC GID FROM ABC If you enter the DEFINE command without an argument all currently defined symbols will be listed and if you enter DEFINE with just a sym bol name then the value of that symbol will be shown DATABASE PROTECTION eBase databases have three levels of Passwords which can be used to secure the data against inadvertent destruction or unauthorized use These passwords allow READ
138. ted Relations represent the static solution to two distinct loading conditions O RESULT Q4S is a Relational Entity containing the same data as the previous Relations using a different organization in which the load ing condition data is stored as a Relational attribute INTRODUCTION eShell Users Manual Note that these two different data forms simply illustrate different data modeling methods there is no need to have both forms to perform any particular access Only the retrieval performance is affected by the modeling method O RESULT BIGREL is a Relational Entity containing a large number of entries which depends on your host computer It is used in the examples presented in Chapter 6 O MODEL KGG is a Matrix Entity that represents the global stiffness matrix of the finite element model The Matrix has the Column major Orientation Compressed Mode Numeric Type real double preci sion RDP and Symmetric Shape The contents of this Matrix are 100 0 200 0 0 0 0 0 Qv 0 0 200 0 300 0 400 0 0 0 0 0 0 0 DU 400 0 500 0 600 0 00 0 0 0 0 600 0 700 0 800 0 0 0 0 0 0 0 0 0 800 0 900 0 1000 0 0 0 0 0 0 0 0 0 1000 0 1100 0 O MODEL TESTFREE is a Freeform Entity containing five Records of varying length each of which is comprised of real single precision RSP data The data are
139. tion you must have opened the database with the ADMINISTRATION privilege When you end your eShell ses sion all open databases are automatically closed It is not necessary to explicitly close each one eQL Command Entry INTRODUCTION Because the eQL language allows you to perform complex operations on the database it is possible for commands to get rather long To support long commands and to allow their entry in a readable and structured manner eQL allows commands to be entered on multiple lines When this is done eQL provides line numbers for the command as it is being entered This is illustrated in the following example Example 1 3 Entering an eQL command on multiple lines eSh SELECT FROM GRID 2 WHERE X 3 0 3 AND Y x 2 0 Note that the command must end with a semicolon Each command line continuation is numbered beginning with 2 The line entered at the prompt is called line 1 eShell performs no action until the complete command including the semicolon has been entered This command is referred to as the Active Command After it is entered the active com mand is saved until you enter the next active command This allows you to modify a command in the event it contains an error or in order to create a new command that is similar to it You may list the active com mand using LIST line 1 TO line n where 1ine 1 represents the first line number to be listed and 1ine n the last If no l
140. uage is its ability to retrieve data from an eBase database This Chapter describes the commands used to retrieve data from Relations The results of such a retrieval are called a Query and the act of the retrieval is often referred to as Querying The flexibility and options available for retrieval of data are of a complex nature Therefore this Chapter is organized in such a manner that suc cessively more advanced uses of the SELECT command are defined and illustrated by many examples It is best to read all of the material thor oughly and to work through the examples using the sample database Data retrieval is accomplished with the SELECT command The general form of this command is RELATION SELECT select list FROM part WHERE part GROUP part ORDER part The select list and FROM part are required The WHERE part GROUP part and ORDER part are each optional but when any or all of them appear in the SELECT command they must appear in the order indicated The richness of this command requires numerous examples The examples which follow are presented in increasing levels of com plexity starting with the simplest form of the command RETRIEVING DATA FROM RELATIONS 4 1 User s Manual 4 2 eShell SELECT attrib list FROM rel name where the attrib list isa list of one or more attribute names sepa rated by commas that are contained in the Relation specified by rel name Example 4 1 Query all of the columns
141. ue to minimize the disk storage requirements COLUMN 4 3 1 5 2 3 4 0 of matrices by storing them in the Compressed mode Unlike the Uncompressed Matrix only the INTRODUCTION 1 5 User s Manual eShell non zero terms of Compressed matrices are stored along with a small amount of control information Consider the Matrix 10 0 0 0 0 0 0 31 55 1 0 0 0 0 0 0 0 3 5 1 5 0 0 2 0 22 23 0 0 0 0 0 0 40 Figure 1 5 illustrates how this data would appear in a Column major Orientation for both the Compressed and Uncompressed Modes Freeform Entities Freeform Entities are a form of internal data representation that can sometimes be used to improve the performance of software applications They are collections of data with only a local Figure 1 6 FREEFORM Entity and transient purpose Most often they are used in a software application that has been de veloped with the eBase applib You may think RECORD1 3 Value 1 Value 53 of Freeform Entities as Fortran random files which have variable length Records as shown in Figure 1 6 Freeform Entities are defined with RECORD32 value a single Schema Component that defines the re cords to be comprised either of a homogeneous data type or of mixed heterogeneous data types RECORD 5 gt Jaloe 5 5 The former called Schematic Freeform Entities may be viewed in eShell as described in Chap ter 7 and they may be exported and imported as described in Chapter 11 Neither
142. uential search which must check each entry Since an attribute of type RSP cannot be indexed it appears that query performance will be slow If you intended to access the data in this manner a simple artifice can be used to allow the creation of an attribute index One way to do this is to model the data as INDEXING RELATIONAL ENTITIES 6 3 Users Manual INDEX PERFORMANCE 6 4 eShell GID TIME TIME STEP DISP X DISP Y DISP Z INT RSP INT RSP RSP RSP 101 0 0 1 0 03 0 02 0 04 102 0 0 1 0 02 0 01 0 02 101 0 1 2 0 05 0 01 0 03 102 0 1 2 0 07 0 03 0 06 Here a new attribute called TIME STEP of type INT has been introduced as a counter for the RSP attribute TIME Now to rapidly access the data the following commands may be used eSh CREATE INDEX ON RESULT TIME STEP Index Created Finally if you were directly accessing individual grid points at specific times efficiency would be maximized by defining a two attribute index eSh gt CREATE INDEX ON RESULT GID TIME STEP Index Created Now any query of the form eSh SELECT FROM RESULT 2 WHERE GID 102 AND TIME STEP 2 Result of query is printed will be able to use the index for rapid access The use of indexes can dramatically improve performance when the Re lational entity is accessed in the order of an attribute index or when entries are selected which have specifi
143. uring a subsequent eShell session as a script file Attributes The columns of a Relational entity Each attribute has a name and a data type associated with it Column major A method of storing a Matrix entity where the number of columns in the matrix is dynamic but the number of rows is fixed Command Buffer area where all the lines of your eQL command are stored pending their execution Compressed Storage Mode Matrix eBase uses an optional data com pression technique to minimize the disk storage requirements of matrices This is called Compressing Only the non zero terms of compressed matri ces are stored along with a small amount of control information See also Uncompressed Storage Mode B 1 User s Manual eShell Current Position The line within the Command Buffer where you may perform command editing Data Modeling The process of designing representations of scientific data Factors to be considered include the quantity of data and the method in which it will be accessed Directory named area of the eBase database which contains entities which are related to each other Entity An Entity is a database object which contains a Name a Schema and a Data Component See also Entity Classes Entity Classes Groups of eBase entities which share the same kinds of schema The four eBase entity classes are Relational entities Matrix enti ties Freeform entities and Stream entities Entry An Entry is a
144. ut resorting to one of the quantifiers ALL ANY or SOME If groups exist then a single value or list of values is returned for each group RETRIEVING DATA FROM RELATIONS eShell Users Manual Example 4 26 Find the maximum grid point identification number used as G3 in the QUAD4 Relation for each property identifi cation number PID eSh SELECT PID MAX G3 FROM QUAD4 2 gt GROUP BY PID 2 Entries Selected This operation is possible because the GROUP part has partitioned the Relation into groups upon which the group operator MAX can function Note that the ORDER part does not allow this type of operation to be performed because it does not partition the data into distinct groups The COUNT function is used to count the number of entries that satisfy the given selection criteria The general form of this function is COUNT M ivi DISTINCT attrib name where the shorthand notation indicates that all entries will be counted If DISTINCT attribute name is specified then the number of entries which have distinct nonnull values for that attribute will be counted Example 4 27 Count the number of QUAD4 elements with a PID of 2 eSh SELECT COUNT FROM QUAD4 WHERE PID 2 1 Entry Selected Example 4 28 Count the number of unique values of PID in Relation QUAD4 eSh gt SELECT COUNT DISTINCT PID FROM QUAD4 COUNT DISTINCT PID 1 Entry Selected RETRIEVING DATA FROM RELATIONS 4 17 Us
145. uter to another US Check with eBase Customer Support at UAI when using DEC VAX VMS or CRAY computers because the computers do not currently use the IEEE standard FILE ENVIRONMENT COMMANDS 11 5 User s Manual eShell This page is intentionally blank 11 6 FILE ENVIRONMENT COMMANDS eShell Users Manual 12 REPORT GENERATION One of the major purposes of eShell is to provide capability for the post processing of engineering analysis data and results The previous Chap ters of this manual have described many methods for manipulating eBase entities This section presents the methods available for generating customized reports suitable for inclusion in design reports FORMATTING COMMANDS Formatting commands allow you to specify customized labels and for mats for reports Specific features include Column Labels and Formats 3 Page Titles O Grouping Commands O Page Control Commands The sections below give detailed definitions of these commands and ex amples of their use COLUMN LABELS AND FORMATS REPORT GENERATION As illustrated previously in this manual selected data are printed using the names of the attributes within the schema as column titles and the data values are printed in the default formats defined within eShell However the results of any Relational query can be presented using descriptive headings and formats selected by the user First consider the standard query results User s Manu
146. value term SET VALUES AT TERM corr id TO values Specifies the new matrix values A 9 User s Manual eShell UPDATE FREEFORM free name SET position TO value list WHERE RECORD rec id Updates or modifies all or part of the data in a Stream entity UPDATE STREAM stream name SET position TO value list Updates or modifies all or part of the data in a Freeform record ALTER rel name ADD new schema list Adds one or more new attributes to an existing Relation Chapter 10 Removing Data from eBase This Chapter describes the eQL commands that are used to remove enti ties and their data from the eBase database RELATION MATRIX FREEFORM STREAM PURGE entity name ALLVER Removes an entity and its data from the database DELETE FROM RELATION rel name WHERE part Deletes selected entries from the named Relation that meet the selection criteria DELETE FROM MATRIX mat name list Deletes selected columns or rows from a Matrix entity DELETE FROM FREEFORM free name list Removes selected Records from a Freeform entity Chapter 11 File Environment Commands A 10 This Chapter describes a class of commands that can modify the file environment under which eShell performs certain operations START file name param list Executes an eQL Script File saved as a host computer file and optionally passes parameters to it SET ARCHIVE TO file name Defines a file on the
147. verhead occurs only once and is well worth the investment if a large number of queries will be made on a specific Rela tion At the same time an index slows down INSERT and UPDATE opera tions because each of the indexes that you have created must also be updated Performance is improved if you purge any indexes which are not being used This is done with the command PURGE INDEX ON rel name attr name list where attr name list is a list of the attributes used in a previously created index for the Relational entity rel name Recall that you may use the DESCRIBE command to obtain a listing of the indexes for the Relation as shown in the following example Example 6 5 Remove the indexes of Relation BIGREL that you created in Example 6 4 eSh DESCRIBE BIGREL Relation TESTEB RESULT BIGREL Schema is Attribute Current Contents x Entries 2 INDEXES EXIST 1 on ATT 2 on ATT1 and ATT2 PURGE INDEX ON BIGREL ATT1 Index has been Purged PURGE INDEX ON BIGREL ATT1 ATT2 Index has been Purged EB database to Clean up your TUTOR Directory to restore your TES its initial state INDEXING RELATIONAL ENTITIES eShell Users Manual 7 RETRIEVING DATA FROM NON RELATIONAL ENTITIES In addition to the powerful querying operations for Relational entities described in the previous Chapter you may also perform queries on the data for Matrix entities Freeform entities and Stream ent
148. width is lengthened to accom modate it Similarly arithmetic expressions may be used as constraints in a WHERE part Example 4 11 Select all element identification numbers from Relation Q4STR 1 where the Normal Y stresses SIGY are at least twice the Normal X stresses SIGX eSh SELECT EID SIGY FROM RESULT Q4STR 1 WHERE 2 SIGY gt 2 0 SIGX 2 00000E 06 1 00000 07 2 Entries Selected Built in arithmetic functions also found in Fortran are available to sup port the most frequently used operators These are shown in Table 4 2 along with the allowable Numeric Types of their arguments The results of each function are coerced to the required Numeric Type Previous sections have illustrated the manner in which a single Relation is queried A special operation called the Join is available to allow the selection of data from more than one Relation and to combine this into a single result The Relationship of entries in two or more Relations is determined by the field values in the entry For example both the QUAD4 Relation and the PSHELL Relation have an attribute called PID the property identification number This commonality of data al lows entries in QUAD4 to be related to those in PSHELL eBase is not a pure Relational database The Relational schema are not independent of the entities This means that it is possible for two Relations to have attributes of the same name which are not in fac from the same doma
149. wing example Example 4 4 Suppose that the Relation QUAD4 was created in a slightly different manner to place the grid point identification numbers G1 G2 G3 and G4 in a single attribute called GRIDS of data type INT and length 4 The following out put would result from the indicated query eSh SELECT EID PID GRIDS FROM QUAD4 4 Entries Sel Individual elements within an array attribute cannot be referenced or selected on an individual basis nor can they be used in any computational manner REFERENCING A PATH DURING THE QUERY The rel name specified in the FROM part of a query may include a full path name in addition to a simple entity name Alternately you may set a default path prior to the query or you may define a global symbol that are used in the name These are shown in the following example RETRIEVING DATA FROM RELATIONS 4 3 User s Manual eShell Example 4 5 Suppose that the Relation QUAD4 resides in the directory BIGPLANE WING The following methods may be used to query the Relation SELECT EID PID GRIDS FROM BIGPLANE WING QUAD4 or cd bigplane wing SELECT EID PID GRIDS FROM QUAD4 or DEFINE PATH bigplane wing SELECT EID PID GRIDS FROM amp PATH QUAD4 QUALIFYING THE SELECTION 4 4 In many cases it is desired to select only those entries in a Relation that satisfy a certain condition or combination of conditions This is accom plished by using the following variation
150. within eShell you must indicate where a database entity may be found within the directory struc ture This is done by specifying the Path to the entity If the Path name begins with a slash then eShell searches for the entity beginning at the root of the directory structure Otherwise eShell begins at the current directory and searches downward For example many eShell commands require that you enter one or more entity names Each entity name may be in one of three forms O It may be a fully qualified name This means specifying the entire directory Path including the database descriptor DB2 A B C MYDATA O It may be an Absolute Directory In this case the specified PATH is used and only the database descriptor is obtained from the current path default If DB2 A B isthe default path Then D E MYDATA refersto DB2 D E MYDATA O It may be a Relative Directory in which case the specified PATH is appended to the default DIRECTORIES AND ENTITIES 2 1 User s Manual eShell If DB2 A B isthe default path Then C MYDATA refersto DB2 A B C MYDATA O A second form of relative directory allows you to follow the directory chain upward by using a double dot to move up one level in the hierarchy If DB2 A B C isthe default path Then X MYDATA refersto DB2 A X MYDATA If you arein the Root Directory the double dot has no effect CREATING DIRECTORIES A newly created eBase database has a single direct
151. y Encountered Also note that the uniqueness check is applied when you perform an UPDATE operation on an indexed Relation INDEXING RELATIONAL ENTITIES eShell Users Manual IMPROVING QUERY PERFORMANCE Indexes for a Relation are only used when you perform a query which is qualified by a WHERE clause In such cases eShell uses the index data to rapidly process the entries in the entity To understand how to model your data for optimum performance consider the following Relation named RESULT GID TIME DISP X DISP Y DISP Z INT RSP RSP RSP RSP 101 0 0 0 03 0 02 0 04 102 0 0 0 02 0 01 0 02 101 0 1 0 05 0 01 0 03 102 0 1 0 07 0 03 0 06 RESULT has five attributes a grid point identification number GID a time TIME and three results values called DISP X DISP Y and DISP_Z Now suppose that you want to perform the following query eSh SELECT FROM RESULT 2 WHERE GID 101 Result of query is printed If there are tens of thousands of entries in RESULT it would take a large amount of time to search through the entries sequentially to extract the desired selection By first creating an index eSh CREATE INDEX ON RESULT GID Index Created the same query can be processed very rapidly On the other hand sup pose you want eSh SELECT FROM RESULT 2 WHERE TIME 0 1 Result of query is printed This query also results in a seq

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