Re: Performance of DOMAINs

From: David Wheeler <david(at)kineticode(dot)com>
To: josh(at)agliodbs(dot)com
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Performance of DOMAINs
Date: 2006-06-22 18:18:12
Message-ID: DDC7B143-465F-4AC6-AE5A-D895A2FD2A1E@kineticode.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

On Jun 21, 2006, at 18:19, Josh Berkus wrote:

> Well, current case-insensitivity hacks definitely aren't compatible
> with
> LIKE as far as "begins with" indexes are concerned.

Yes, currently I use LOWER() for my indexes and for all LIKE, =, etc.
queries. This works well, but ORDER by of course isn't what I'd like.
That's one of the things that Elein's email domain addresses, albeit
with a USING keyword, which is unfortunate.

> Of course, floating
> LIKEs (%value%) are going to suck no matter what data type you're
> using.

Yes, I know that. :-) I avoid that.

> I created an operator for CI equality ... =~ ... which performs
> well on
> indexed columns. But it doesn't do "begins with".

Oops. So how could it perform well on indexed columns?

> ITEXT is a TODO, but there are reasons why it's harder than it looks.

I'm sure. I should bug potential future SoC students about it. ;-)

Best,

David

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message David Wheeler 2006-06-22 18:18:48 Re: Performance of DOMAINs
Previous Message David Wheeler 2006-06-22 18:11:36 Re: Performance of DOMAINs