On Mon, Mar 30, 2009 at 1:42 PM, wrote:
On Mon, Mar 30, 2009 at 12:42 PM,  wrote:
Arguably in this case the actual query should run faster than the
EXPLAIN
ANALYZE version, since the cache is hot. (Though that'd only likely
shave
a few dozen ms off the runtime)
Joining a lot of tables together?  Could be GEQO kicking in.
Only if I get different query plans for the query depending on whether
it's being EXPLAIN ANALYZEd or not. That seems unlikely...
Yes, you can. In fact you often will. Not because it's being
explained or not, just because that's how GEQO works.
Ouch. I did *not* know that was possible -- I assumed that the plan was
deterministic and independent of explain analyze. The query has seven
tables (one of them a temp table) and my geqo_threshold is set to 12. If
I'm reading the docs right GEQO shouldn't kick in.

-Dan

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grouppgsql-performance @
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postedMar 30, '09 at 5:57p
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