RE: CQE changes between v5r2 and v5r4? Query/400 Performance.

Are the poor performing ones targeting an SQL view by any chance? In that
case, I think SQE might get involved for the SQL in the view itself.
Are any keyed LFs or indexes invalid or missing?
Any changes in memory pool allocations?

Not sure what else to look at ... dbmon, STRDBG query optimizer messages,
Visual Explain would be the tools to use to try and figure it out.

Hth, Elvis

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-----Original Message-----
Subject: CQE changes between v5r2 and v5r4? Query/400 Performance.

All,

I was under the impression that the CQE had no changes between v5r2 and
v5r4; that all the enhancements (ie. changes) went into the SQE.

However, now that we've upgrade to v5r4, I've had a few complaints from both
users and IT Business Analysts saying that some Query/400 queries are
performing much poorer now than they did in the past.

I expected to see changes in the performance of (some) SQL queries that used
the SQE. But since Query/400 queries use the CQE, I didn't expect any
performance differences.

Has anybody else had this issue?

I'm trying to take a look at some of the offenders, but thought I'd post
here at the same time.

Charles