sql join performance issue -- MIDRANGE-L

Subject: sql join performance issue
From: <franz400@xxxxxxxxxxxx>
Date: Mon, 30 Aug 2010 14:32:57 -0400
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Reviewing a performance issue, .net app opening a cursor that has sql selects that are inserted into a temp table. Two large orders files (FILEA & FILEB) and a temp file (FILEC) with the single record of the Cust and Region selected.
FILEA inner join FILEB on aORDER = bORDER inner join FILEC on aCUST = cCUST,aREGION = cREGION

Visual Explain is saying FILEB is a table scan even though it has an index of ORDER (there is 1 rec per order in "a" and also "b").
Not understanding why it needed a table scan of a million recs to get 80 records for a cust/region

Jim Franz

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Follow-Ups:

Re: sql join performance issue , Charles Wilt
RE: sql join performance issue , DeLong, Eric
RE: sql join performance issue , Morgan, Paul

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