Re: indexing with lower(...) -> queries are not optimised very well - Please Help - Mailing list pgsql-general

From Martin Hampl
Subject Re: indexing with lower(...) -> queries are not optimised very well - Please Help
Date
Msg-id A4CA6B94-1FFE-11D8-8431-000393674318@gmx.de
Whole thread Raw
In response to Re: indexing with lower(...) -> queries are not optimised very well - Please Help  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Am 21.11.2003 um 06:54 schrieb Tom Lane:

> Martin Hampl <Martin.Hampl@gmx.de> writes:
>>   Index Scan using word_lower_idx on token  (cost=0.00..98814.08
>> rows=25382 width=16)
>>     Index Cond: (lower((word)::text) = 'saxophone'::text)
>
> The rows estimate (and therefore also the cost estimate) is a complete
> guess in this situation, because the system keeps no statistics about
> the values of lower(word).  Improving this situation is on the TODO
> list.

Thanks a lot for your answer.

Any idea about when this situation will be improved? Until then I have
to find a work around... any suggestions?

Regards,
Martin.


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