Date: Thu, 21 Jun 2007 12:04:25 +0200
From: "A. Kretschmer" <andreas.kretschmer@schollglas.com>
To: pgsql-sql@postgresql.org
Subject: Re: Results per letter query
Message-ID: <20070621100425.GH1405@a-kretschmer.de>
References: <467A406A.3060907@androme.es>
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am  Thu, dem 21.06.2007, um 11:10:02 +0200 mailte Dani Castaños folgendes:
> Hi!
> 
> I'm trying to build a query to get if there is an occurrence for a field 
> for each alphabetical letter.
> My first thought to know it was to do something like:
> 
> SELECT COUNT(field) FROM table WHERE UPPER( field )  LIKE UPPER( 'A%' ) 
> LIMIT 1;
> SELECT COUNT(field) FROM table WHERE UPPER( field )  LIKE UPPER( 'B%' ) 
> LIMIT 1;
> SELECT COUNT(field) FROM table WHERE UPPER( field )  LIKE UPPER( 'C%' ) 
> LIMIT 1;
> ...
> and so on...
> 
> Is there any way to do it in only one query??

I'm not sure if i understand you correctly, sorry, if not.

test=*# select * from w;
   t
--------
 test
 foo
 bar
 foobar
(4 rows)

test=*# select chr(x), count(1) from generate_series(65,90) x, w where
upper(substring (w.t from 1 for 1)) ~ chr(x) group by 1;
 chr | count
-----+-------
 T   |     1
 B   |     1
 F   |     2
(3 rows)


Andreas
-- 
Andreas Kretschmer
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