Generating the Subschema Information Area (SSIA) with BGSSIA

The compiled subschema description is available in DBCOM as the end product of compilation by the DDL compiler. The BGSSIA utility routine requires this description in order to generate the Subschema Information Area (SSIA).

The SSIA is stored in the DBDIR as a record of the internal record type SSIA-RECORD.The SSIA contains subschema information needed by the DBH so that it can access the database. The information can be printed out by means of the DISPLAY statement in BGSSIA or by means of the BPSIA utility routine (see "SSIA PRINT REPORT" in the "Recovery, Information and Reorganization" manual).

When required, BGSSIA automatically extends the DBDIR and DBCOM of the database being processed or the DBTTs of the record types in the DBCOM. For details, please refer to the "Database Operation" manual, Automatic realm extension by means of utility routines.

At startup BGSSIA takes into account any assigned UDS/SQL pubset declaration (see the "Database Operation" manual, Pubset declaration job variable). Faulty assignment leads to the program aborting.

During execution BGSSIA works with the linked-in DBH.

Figure 14: System environment for BGSSIA

Statements for BGSSIA

Statement	Default value	Meaning
GENERATE SUBSCHEMA   subschema-name OF    SCHEMA schema-name	-	Optional; subschema-name: name of the subschema schema-name: name of the schema Checks whether an SSIA is available for a specific subschema and generates an SSIA with information on realms, record types and sets lists of individual items lists of all names contained in the subschema.
DELETE SUBSCHEMA   subschema-name OF   SCHEMA schema-name	-	Optional; Deletes a previously generated SSIA from the DBDIR.
REGENERATE SUBSCHEMA   subschema-name OF   SCHEMA schema-name	-	Optional; Deletes the old SSIA and generates a new SSIA (combines DELETE and GENERATE functions). Suitable for correction of a subschema.
DISPLAY[ SUBSCHEMA   subschema-name OF   SCHEMA schema-name]	-	Optional; Can only be used in conjunction with the GENERATE or REGENERATE statement. To print out SSIA, DISPLAY by itself is sufficient.
END	-	Mandatory; Terminates entry of statements.

Table 16: Statements for BGSSIA

Command sequence to start BGSSIA

It is assumed for the command sequence described here that UDS/SQL was installed with IMON (see section "START commands for the UDS/SQL programs").

01 /ADD-FILE-LINK LINK-NAME=DATABASE,FILE-NAME=dbname.DBDIR

02 /SELECT-PRODUCT-VERSION PRODUCT-NAME=UDS-SQL,VERSION=version,SCOPE=*TASK

03 /START-UDS-BGSSIA

04 bgssia-statements

05 END

02	The version-independent module of the linked-in DBH of the relevant version is loaded dynamically (see the section entitled "Compiling, linking and loading UDS/SQL-TIAM appliction programs" in the "Application Programming" manual).
03	The UDS/SQL utility routine can also be started with the alias BGSSIA.

Example

/ADD-FILE-LINK LINK-NAME=DATABASE,FILE-NAME=TRAVEL.DBDIR 
/SELECT-PRODUCT-VERSION PRODUCT-NAME=UDS-SQL,    VERSION=02.9B00 
/START-UDS-BGSSIA
***** START        BGSSIA       (UDS/SQL  V2.9  1801 )    2019-01-29   09:27:00
GENERATE SUBSCHEMA RESERVATION OF SCHEMA TRAVEL-AGENCY                  
DISPLAY                                                                 
END                                                                     
%  UDS0215 UDS STARTING UDS/SQL V2.9 (LINKED-IN), DATE=2019-01-29 (ILL2038,09:27:00/4TE7) 
%  UDS0746 UDS PUBSET DECLARATION (CURRENT) FOLLOWS (ILL1746,09:27:00/4TE7) 
4TE7: UDS-PUBSET-JV:  :IUDS:$XXXXXXXX.PUBSDECL.PUBS                         
4TE7: PUBSETS:        IUDS
4TE7: DEFAULT PUBSET: IUDS
4TE7: ------------------------------------------
*** SSIA GENERATION NORMALLY ENDED. 
*GENERATION OF ITEM-TABLE AND NAME-TABLE STARTED. 
*GENERATION OF ITEM-TABLE AND NAME-TABLE FINISHED.
%  UDS0758 NUMBER OF DML-STATEMENTS AND I/O COUNTERS PER DATABASE  (ILL1758,09:27:00/4TE7) 
 4TE7: DATABASE NAME      DMLS   LOG READ  PHYS READ  LOG WRITE PHYS WRITE
 4TE7: -------------------------------------------------------------------
 4TE7: TRAVEL             1800       2529         76        296         27
%  UDS0213 UDS NORMAL SYSTEM TERMINATION WITH ************1800 DML-STATEMENTS 2019-01-29
(ILLY033,09:27:00/4TE7)
 
***** DIAGNOSTIC SUMMARY OF BGSSIA
 
              NO WARNINGS
              NO ERRORS 
              NO SYSTEM-ERRORS
 
***** END OF DIAGNOSTIC SUMMARY
***** NORMAL END   BGSSIA       (UDS/SQL  V2.9  1801 )     2019-01-29   09:27:00