Tom Lane wrote:
"Craig A. James" <[EMAIL PROTECTED]> writes:
It looks to me like the problem is the use of nested loops when a hash
join should be used, but I'm no expert at query planning.

Given the sizes of the tables involved, you'd likely have to boost up
work_mem before the planner would consider a hash join.  What nondefault
configuration settings do you have, anyway?

shared_buffers = 20000
work_mem = 32768
effective_cache_size = 300000

This is on a 4GB machine.  Is there a guideline for work_mem that's related to table 
size?  Something like, "allow 2 MB per million rows"?

I'm also curious why the big difference between my "Query #1" and "Query #2".  
Even though it does a nested loop, #2's outer loop only returns one result from a very tiny table, 
so shouldn't it be virtually indistinguishable from #1?

Thanks,
Craig

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