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Re: Query Optimizer makes a poor choice

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>> I haven't had a chance to experiment with the SET STATISTICS, but 
that
>> got me going on something interesting...
>>
>> Do these statistics look right?
>>
>> # SELECT attname, n_distinct, most_common_vals, histogram_bounds FROM
>> pg_stats WHERE tablename = 'cards';
>>
>...
>> "card_set_id"   905
>> "{5201,3203,3169,5679,5143,5204,5655,4322,5236,4513}"
>> "{4,3080,3896,4349,4701,5179,5445,5706,6003,6361,6784}"
>
>This looks promising, because n_distinct is low enough that you can
>cover almost all values with statistics.
>raise the statistics and ANALYZE. should help.
>(NOTE NOTE NOTE: assuming that the distribution is even)
>
>
>...
>but one thing we see for sure is that you have not tuned your
>PostgreSQL instance :-)
>I would recommend pgtune, -> pgfoundry.org/projects/pgtune/
>it covers most important stuff, *including* default_statistics_target.
>
>
>
>Filip
>

I just tried the set statistics on our test system with essentially the 
same end result. 

I'm beginning to think the answer is to just avoid LIMIT.

Tyler



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