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Message Posted: Wed, 16 Jul 2003 @ 13:36:54 GMT

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If you are on R5 (or considering it) the Join Elimination (JE) feature might help you here. If you are able to build a view that joins all the Reference tables to the CALL_HIST and your users only Select columns from some/few of the Reference table columns the optimizer should remove those join requirements from the work steps. Here is an excerpt from a presentation for R5.

"....

* Description

- Redundant primary key, foreign key joins (PK-FK joins) are removed by the optimizer

- Works with regular and soft RI

* Customer Benefit

- Improved performance for queries that perform PK-FK Join by default without requiring columns form the PK table

- Assume that the joins between tables are Pk-FK joins - example a join of a transaction table to a set of dimension tables:

* If a view joins several tables, but the user of the view references columns from only one, then the joins are wasted time and resources and can be eliminated

* If a query tool or application joins all the dimension tables for every query but frequently references only columns from one or a subset of the tables, then the other joins are wasted effort and resources and can be eliminated

...."

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