Re: SQL performance

Hi Charles,


Von meinem iPhone gesendet

Am 23.08.2024 um 21:10 schrieb Charles Wilt <charles.wilt@xxxxxxxxx>:

If you switch to PREPARE and EXECUTE, let us know the effect.

Normally static is better, but I've seen and IBM has confirmed that there
are some instances where dynamic performs better.

Yes - a dynamically prepared SQL statement, with ? placeholders and EXECUTE ... USING ... can have a better performance than a static SQL - but I doubt, that it will be significant.

The biggest speed boost would be, the integrate this "CHAIN" like SQL fetch as a JOIN in the "upstream" SQL cursor.

I never had a case where that wouldn't be possible. With conditional JOINs, CASE WHEN ELSE, CTEs and window functions we have all the tools to replace 2 dozens of SETLLs, READs and CHAINs with one SQL SELECT statement.

So reengineering the application still is the best option. And I would invest my time into that - not into fiddling out some seconds with different SQL techniques.

Regards,
Daniel