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Re: comparison of 8.3.10 to 8.3.14 reveals unexpected difference in explain plan - Mailing list pgsql-performance

From Mark Rostron
Subject Re: comparison of 8.3.10 to 8.3.14 reveals unexpected difference in explain plan
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Msg-id FD020D3E50E7FA479567872E5F5F31E3046520C466@ex01.corp.ql2.com
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In response to Re: comparison of 8.3.10 to 8.3.14 reveals unexpected difference in explain plan  (Greg Smith <greg@2ndquadrant.com>)
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> It would be easier to suggest what might be wrong if you included "EXPLAIN ANALYZE" output instead of just EXPLAIN. 

> It's not obvious whether 8.3 or 8.4 is estimating things better.

Thanks for reply man

Turns out random_page_cost was set low in the 8.3.10 version – when I reset it to 4(dflt), the explain plans are the same.

We’ll double check our other queries, and then I’ll see if I can reset it to dflt for the database.

 

 

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