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Re: Forcing use of a particular index
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* Re: Forcing use of a particular index
@ 2005-06-27 22:40  Jacques Caron <jc@directinfos.com>
  parent: Karl O. Pinc <kop@meme.com>
  0 siblings, 0 replies; 2+ messages in thread

From: Jacques Caron @ 2005-06-27 22:40 UTC (permalink / raw)
  To: Karl O. Pinc <kop@meme.com>; +Cc: pgsql-performance

Hi,

At 01:16 28/06/2005, Karl O. Pinc wrote:
>http://www.postgresql.org/docs/8.0/static/indexes-examine.html
>
>Says:
>
>"If you do not succeed in adjusting the costs to be more
>appropriate, then you may have to resort to forcing index
>usage explicitly."
>
>Is there a way to force a query to use a particular index?

Not that I know of.

>If not, what does this sentence mean?

That you can force the planner to use an index (any one) over not using an 
index (and using seq scans instead) by setting enable_seqscan to off.

Jacques.





^ permalink  raw  reply  [nested|flat] 2+ messages in thread

* Forcing use of a particular index
@ 2005-06-27 23:16  Karl O. Pinc <kop@meme.com>
  0 siblings, 1 reply; 2+ messages in thread

From: Karl O. Pinc @ 2005-06-27 23:16 UTC (permalink / raw)
  To: pgsql-performance

http://www.postgresql.org/docs/8.0/static/indexes-examine.html

Says:

"If you do not succeed in adjusting the costs to be more
appropriate, then you may have to resort to forcing index
usage explicitly."

Is there a way to force a query to use a particular index?
If not, what does this sentence mean?

Thanks.


Karl <kop@meme.com>
Free Software:  "You don't pay back, you pay forward."
                  -- Robert A. Heinlein




^ permalink  raw  reply  [nested|flat] 2+ messages in thread

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