Re: Sub-optimal plan chosen

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От bricklen
Тема Re: Sub-optimal plan chosen
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Msg-id 33b743250909101012m4dbc2390wedfe8869f61a1488@mail.gmail.com
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Ответ на Re: Sub-optimal plan chosen  (bricklen <bricklen@gmail.com>)
Ответы Re: Sub-optimal plan chosen
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On Thu, Sep 10, 2009 at 10:07 AM, bricklen <bricklen@gmail.com> wrote:
On Thu, Sep 10, 2009 at 10:02 AM, Robert Haas <robertmhaas@gmail.com> wrote:
On Thu, Sep 10, 2009 at 12:56 PM, bricklen <bricklen@gmail.com> wrote:
> On Thu, Sep 10, 2009 at 8:43 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>
>> bricklen <bricklen@gmail.com> writes:
>> > Is there any other data I can provide to shed some light on this?
>>
>> The table and index definitions?
>>
>> The straight indexscan would probably win if the index column order
>> were ofid, date instead of date, ofid.  I can't tell if you have
>> any other queries for which the existing column order is preferable,
>> though.
>>
>>                        regards, tom lane
>
>
> Changing the order of the WHERE predicates didn't help.

He's talking about the index definition, not the WHERE clause.  The
order of the WHERE clause is totally irrelevant.


Ah, sorry, missed that.


I just created a new index as Tom said, and the query *does* use the new index (where ofid precedes date in the definition).

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