Re: How to retrieve N lines of a text field.

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Chris Travers" <chris(at)travelamericas(dot)com>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: How to retrieve N lines of a text field.
Date: 2004-01-29 15:50:21
Message-ID: 22882.1075391421@sss.pgh.pa.us
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"Chris Travers" <chris(at)travelamericas(dot)com> writes:
> However, this always selects every line but the final one (because %\n seems
> to be interpreted to be the largest possible string, while I want it to be
> the smallest possible string).

I don't think you can solve this in SQL99 regular expressions, but
if you use the POSIX-style regex operators, you can write something
like "[^\n]*\n" to match exactly one line. There are other features
that might help too, such as the counted-match operator "{n}".
Read the man page.

BTW, I bought a copy of the O'Reilly book "Mastering Regular
Expressions" a couple years ago, and it is worth every penny
if you do much of anything with regexes.

regards, tom lane

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