Re: Forcing query to use an index

On Monday, Mar 3, 2003, at 15:21 US/Pacific, Josh Berkus wrote:

> Micheal,
>
> Don't forget to run ANALYZE as well; this does not require a table 
> lock.

Yes, I have a cron job that runs a "vacuum analyze" once every other 
hour.

>> Does using "set enable_seqscan = off" impact anything else on the
>> system, or is it connection-specific?  Is this the recommended way of
>> doing this, or is there another way of coercing Postgres into using
>> indexes?  I'm making these queries from Perl code running in an XSP
>> page, so I'm not sure how flexible this option would be from a
>> developer point of view.
>
> Setting enable_seqscan=off is just for testing purposes, to see if the 
> planner
> is making a wrong decision so that you can adjust your .conf params, 
> query,
> and/or indexes to suit.  The setting is *not* intended as a production
> solution.

*phew*  good.  Now that I know the planner is making a bad choice, 
where do I go from here?  Should I RTFM?

Also, the query values in the configuration file that the planner uses, 
are those machine-specific or are the defaults the recommended values?