Re: How to force PostgreSQL using an index
| От | Tom Lane |
|---|---|
| Тема | Re: How to force PostgreSQL using an index |
| Дата | |
| Msg-id | 20580.1140044567@sss.pgh.pa.us обсуждение исходный текст |
| Ответ на | Re: How to force PostgreSQL using an index ("Owen Jacobson" <ojacobson@osl.com>) |
| Список | pgsql-sql |
"Owen Jacobson" <ojacobson@osl.com> writes:
> On Wed, Feb 15, 2006 at 04:58:54PM -0500, Daniel Caune wrote:
>> I see, but that doesn't explain whether it is possible to specify the
>> index to use. It seems that those options just force PostgreSQL using
>> another plan.
> Drop the simple index and re-create it when you're done?
BTW, the cute way to do that is
BEGIN;DROP INDEX unwanted;EXPLAIN ANALYZE whatever...;ROLLBACK;
No need to actually rebuild the index when you are done.
This does hold an exclusive lock on the table for the duration of your
experiment, so maybe not such a good idea in a live environment ... but
then again, dropping useful indexes in a live environment isn't a good
idea either, and this at least reduces the duration of the experiment by
a good deal.
regards, tom lane
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