From: Jeff Frost <jeff@frostconsultingllc.com>
To: pgsql-sql@postgresql.org
Subject: finding columns that have three or fewer distinct characters
Date: Wed, 5 Mar 2008 09:33:53 -0800 (PST)
Message-ID: <Pine.LNX.4.64.0803050912570.4804@discord.home.frostconsultingllc.com> (raw)
I've got an interesting one...I'm trying to find columns that have three or
fewer distinct characters (for example, "aaaaaaaaaa"). Wondering if I need to
write a function or if someone has an idea how to do it with built in
functions and/or pattern matching?
I think the thing to do would be to lowercase everything, then remove all
duplicate chars and spaces, then use length() on that, but it's not obvious to
me how I might remove the duplicate chars with the pattern matching support
in the docs.
--
Jeff Frost, Owner <jeff@frostconsultingllc.com>
Frost Consulting, LLC http://www.frostconsultingllc.com/
Phone: 650-780-7908 FAX: 650-649-1954
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To: pgsql-sql@postgresql.org
Cc: jeff@frostconsultingllc.com
Subject: Re: finding columns that have three or fewer distinct characters
In-Reply-To: <Pine.LNX.4.64.0803050912570.4804@discord.home.frostconsultingllc.com>
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