| From: | "Dmitry Teslenko" <dteslenko(at)gmail(dot)com> |
|---|---|
| To: | pgsql-general(at)postgresql(dot)org |
| Subject: | Re: Strange query plan |
| Date: | 2008-08-14 11:48:49 |
| Message-ID: | 91325fec0808140448l6cf2db2di4ea4ac23e901b361@mail.gmail.com |
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| Lists: | pgsql-general |
On Thu, Aug 14, 2008 at 15:30, Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:
> Am Thursday, 14. August 2008 schrieb Dmitry Teslenko:
>> SELECT SUM(...) FROM table1 WHERE field3 = 'ABC' AND field1 <> 1
>> GROUP BY field2
>>
>> And planner picks up a sequential scan of a table. Why does he?
>
> Presumably because it thinks it is the best plan, and I see no reason to doubt
> that outright. You might get better performance with an index on field3.
>
Why then idx2 on field1 and field3 don't help here?
--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
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