Date: Sun, 28 Oct 2007 12:42:47 +0100
From: Andreas Kretschmer <akretschmer@spamfence.net>
To: pgsql-sql@postgresql.org
Subject: Re: Removing whitespace using regexp_replace
Message-ID: <20071028114247.GA1327@KanotixBox>
References: <fg1ra3$ehj$1@ger.gmane.org>
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Thomas Kellerer <spam_eater@gmx.net> schrieb:

> Hi,
> 
> I have a column with the datatype "text" that may contain leading 
> whitespace (tabs, spaces newlines, ...) and I would like to remove them all 
> (ideally leading and trailing).

You can use trim() for that:

select 'x' || trim(both '\t' from trim(both ' ' from ' \t\tfoo bar  ')) || 'x';

(for testing with 'x' around the result)


> 
> I tried
> 
> SELECT regexp_replace(myfield, '\A\s*', '')
> FROM mytable;

For regexp_replace() you need an extra parameter 'g' like below:

test=*# select 'x' || regexp_replace(regexp_replace(' \t\tfoo bar  ', '^[ \t]+','','g'),'[ \t]+$','','g') || 'x';
                                                                                   ^^^               ^^^


Andreas
-- 
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