Re: Help - SQL creating indexes when not necessary.

[Larry Bolhuis <lbolhui@xxxxxxx>]

Walden,

  What OS/400 release are you running?  Recently I have been working
with a customer on a problem with V4R2 that is similair to this.  The
same Debug message appears and if we build that access path in advance
it will use it.  Another symptom is that if we delete the access path we
exect to be used and then rebuild it, SQL will use it THE FIRST TIME
ONLY then revert back to 'acting improperly'.  This was a known problem
with Multiple CPU systems and a PTF was available, but we were
experiencing it on a 600.  The fix was still in development as of a
couple weeks ago.

HTH - Larry Bolhuis
      Arbor Solutions, Inc
      lbolhui@ibm.net


Walden Leverich wrote:
> 
> OK folks, what am I missing?
> I have an index over a physical keyed by BVBYST, BVBWNB, BVBZST,
> BVBVNB with a sort sequence of *HEX and a language of ENU. There is no
> select/omit on this logical, the access path is valid and maintenance
> is immed. There are 125000 index entries. STRSQL's sort sequence is
> set to *JOB and my job's sequence is set to *HEX, similarly, STRSQL's
> language is *JOB and my job's language is ENU.
> I issue the following SQL and SQL proceeds to build an index over
> UPBVREP.
> SELECT AEADST, AEAJNB, AEA1NB, count(*) FROM upbvrep, upaerep WHERE
> aeadst = bvbyst and aeajnb = bvbwnb GROUP BY aeadst, aeajnb, aea1nb
> HAVING count(*) > 0
> The debug message (CPI4321) in the joblog says 'Temporary access path
> built.... using key fields BVBYST, BVBWNB using sequence table of
> QLA10025S...' which is the CCSID 37 shared sort sequence table. Why is
> SQL using this table to build the index? If SQL was to use *HEX, as it
> should, then it could use an existing index to perform the join. What
> gives?
> -Walden
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