Subject | Re: [Firebird-Architect] Composite index optimizer fails |
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Author | Daniel Rail |
Post date | 2003-05-12T10:54:39Z |
Hello Skopalik,
Monday, May 12, 2003, 3:59:33 AM, you wrote:
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Best regards,
Daniel Rail
Senior System Engineer
ACCRA Group Inc. (www.accra.ca)
ACCRA Med Software Inc. (www.filopto.com)
Monday, May 12, 2003, 3:59:33 AM, you wrote:
> I found two situation, where optimizer use bad plan or when FB lost speed.Which version of Firebird are you using? And, on which platform?
> I not need help, I only report tips for improvement FB server.
> First (SQL example sql1):
> AB indexd is needed for Max/Min functions in real database.
> FB select index AB, but if I plan manualy index AA, avarege speed was incresed.
> Second (SQL examlpe sql2):
> Slow evaluating of IN (BETWEEN, OR, ...) clausule.
> When I roll up into UNIONS speed was radicaly incresed.
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Best regards,
Daniel Rail
Senior System Engineer
ACCRA Group Inc. (www.accra.ca)
ACCRA Med Software Inc. (www.filopto.com)