Horton

Re: How to get around LIKE inefficiencies?

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Philip Warner <pjw@rhyme.com.au>, The Hermit Hacker <scrappy@hub.org>, pgsql-hackers@postgresql.org
Date: 2000-11-06T03:53:57Z
Lists: pgsql-hackers 
I am adding a new TODO item:

	* Add SET PERFORMANCE_TIPS option to suggest INDEX, VACUUM, VACUUM
	  ANALYZE, and CLUSTER

Seems we should be able to emit NOTICE messages suggesting performance
improvements.



> Philip Warner <pjw@rhyme.com.au> writes:
> > Could you trick it into not using the index (AND using the other strategy?)
> > by using a calculation:
> 
> >    AND ( (url.url || ' ') LIKE 'http://www.postgresql.org/% ');
> 
> > it's a bit nasty.
> 
> Looks like a great kluge to me ;-)
> 
> 			regards, tom lane
> 


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