Re: Very slow queries on 8.1

int4, not null and the index is unique.  I even tried clustering on it
to no avail.

codeWarrior wrote:

>What is the data type for "signum" ???
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>"David Rysdam" <drysdam@ll.mit.edu> wrote in message
>news:437CA40A.8020507@ll.mit.edu...
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>>I'm porting an application from Sybase and I've noticed that similar
>>application functions take 2 to 3 times longer on postgres than they used
>>to on the same machine running under Sybase.  I've tried changing various
>>"performance tuning" parameters, such as shared_buffers,
>>effective_cache_size, etc but there's little or no effect.  I'm beginning
>>to think there's a deeper root cause to the slowness.
>>
>>Right now, I'm working on a test case that involves a table with ~360k
>>rows called "nb.sigs".  My sample query is:
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>>select * from nb.sigs where signum > 250000
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>>With no index, explain says this query costs 11341.  After CREATE INDEX on
>>the signum field, along with an ANALYZE for nb.sigs, the query costs 3456
>>and takes around 4 seconds to return the first row.  This seems extremely
>>slow to me, but I can't figure out what I might be doing wrong.  Any
>>ideas?
>>
>>(If necessary, I can write an entire script that creates and populates a
>>table and then give my performance on that sample for someone else to
>>check against.)
>>
>>---------------------------(end of broadcast)---------------------------
>>TIP 6: explain analyze is your friend
>>
>>
>>
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