RE: Query Optimizer

[PaulMmn <PaulMmn@xxxxxxxxxxxxx>]

>The optimizer can be pretty *&%$ stupid at times.  There are situation when
>I *know* that a certain logical would work just dandy, but the optimizer
>builds a temporary index anyway.  Sometimes I could write, compile, and run
>an RPG program to do the same thing in less time than it takes for the index
>to build.  :(

>Ken
>Southern Wine and Spirits, Inc.


Our resident Query guru has done magical things with Query and large files.

The most important rules are:

        (1) Your first queries must select/omit records from immense files
to work files

        (2) DO NOT SORT as you select records from immense files.

By following these 2 rules (and using intermediate work files and multiple
queries) he has been able to reduce query processing time from days (well,
hours) to minutes.

--Paul E Musselman
PaulMmn@ix.netcom.com


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