Analyzing Queries with GENPLAN [ ALLBASE/SQL Performance Guidelines ] MPE/iX 5.0 Documentation
ALLBASE/SQL Performance Guidelines
Analyzing Queries with GENPLAN
The GENPLAN statement can be useful in determining the way to write a
SELECT, UPDATE, or DELETE statement for maximum performance. GENPLAN
lets you see the optimizer's access plan for one ALLBASE/SQL statement at
a time. Issue the GENPLAN statement in ISQL, then simply do a SELECT on
the temporary table SYSTEM.PLAN within the same transaction. A
knowledgeable user may be able to use this information to formulate
queries differently or make other design changes to improve performance.
Whenever users have a performance concern about a query, they can use the
GENPLAN statement to generate the access plan for the query and display
the plan information by doing a SELECT on the temporary table
SYSTEM.PLAN. By using GENPLAN and SELECT statements, users can easily
investigate the performance question.
Refer to the ALLBASE/SQL Release F.0 Application Programming Bulletin
chapter, "Analyzing Queries with GENPLAN," and the ALLBASE/SQL Reference
Manual for more information about the GENPLAN statement.
MPE/iX 5.0 Documentation