On Jun 22, 2006, at 2:23 PM, Tom Lane wrote:
"Relyea, Mike" <[EMAIL PROTECTED]> writes:
I've zipped the results of EXPLAIN INSERT INTO "tblSummary" SELECT *
FROM "qrySummary"; for my case.  It's a zip file that I've renamed to
.txt in order to get around the attachment being blocked by certain mail
servers.

Egad, what a mess :-(.  By my count you have 89 hash joins, 24 sorts,
and 8 hash aggregations in there.  In total these will feel authorized
to use 121 times work_mem.  Since you've got work_mem set to 256 meg,
an out-of-memory condition doesn't seem that surprising.  You need to
make work_mem drastically smaller for this query. Or else break it down
into multiple steps.

Except won't the sorts pull in all data from their underlying node before proceeding, which should free the memory from those underlying nodes? If so, it looks like it's not nearly as bad, only taking about 20x work_mem (which of course still isn't great...)
--
Jim C. Nasby, Sr. Engineering Consultant      [EMAIL PROTECTED]
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461



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