Reply-To: <gnanam@zoniac.com>
From: "Gnanakumar" <gnanam@zoniac.com>
To: "'Richard Huxton'" <dev@archonet.com>
Cc: <pgsql-performance@postgresql.org>
References: <004601cbcc14$acfe99d0$06fbcd70$@com>
	<4D58D752.2000100@archonet.com>
	<004701cbcc18$c54c8980$4fe59c80$@com>
	<4D58DC35.8010007@archonet.com>
In-Reply-To: <4D58DC35.8010007@archonet.com>
Subject: Re: How to boost performance of queries containing pattern matching
	characters
Date: Mon, 14 Feb 2011 13:16:07 +0530
Organization: Zoniac Software Private Limited
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> If you really need to match all those options, you can't use an index. A 
> substring-matching index would need to have multiple entries per 
> character per value (since it doesn't know what you will search for). 
> The index-size becomes unmanageable very quickly.

> That's why I asked what you really wanted to match.
To be more specific, in fact, our current application allows to delete
email(s) with a minimum of 3 characters.  There is a note/warning also given
for application Users' before deleting, explaining the implication of this
delete action (partial & case-insensitive, and it could be wide-ranging
too).

> So, I'll ask again: do you really want to match all of those options?
Yes, as explained above, I want to match all those.