SQL Optimizer Issue -- MIDRANGE-L

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Subject: SQL Optimizer Issue
From: Mark Allen <allenmar@xxxxxxxxx>
Date: Fri, 14 Oct 2005 13:14:49 -0700 (PDT)
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Posted for a colleague:
 
What I was told:  A SEQUEL select statement is run over a very large (50-60 
Million records), select by name and a plan field.  MOST of the time results 
are returned quickly but for "some" names the statement does not use the 
existing index and thus creates one, which causes about a 20-30 minute response 
time.  IBM support to date has not been able to help and they ahve submitted a 
PMR to IBM but no response yet and it is becoming (is) an issue.
 
Example:
 
Name=Smith   Plan=B, quick response
Name=Jones Plan=C, takes forever
 
I was told that they have also tried it as a straight interactive SQL and get 
the same issue.  They have not been able to find any rhyme or reason as to why 
"some" names/plan combinations take so long.  Anyone run across this or have 
any ideas?

                
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Follow-Ups:

RE: SQL Optimizer Issue , Elvis Budimlic
Re: SQL Optimizer Issue , Pete Hall
Re: SQL Optimizer Issue , rob

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