From: Bruce Momjian <maillist@candle.pha.pa.us>
Message-Id: <199804231736.NAA29768@candle.pha.pa.us>
Subject: Re: [HACKERS] Re: [INTERFACES] retrieving varchar size
To: hannu@trust.ee (Hannu Krosing)
Date: Thu, 23 Apr 1998 13:35:43 -0400 (EDT)
Cc: hannu@trust.ee, byronn@insightdist.com, pgsql-hackers@postgreSQL.org,
	pgsql-interfaces@postgreSQL.org
In-Reply-To: <353F7A47.3C8D677F@sid.trust.ee> from "Hannu Krosing" at Apr 23,
	98 08:28:39 pm
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> 
> In the latter case, I would suggest an additional SQL command for open
> cursors,
> or a pseudo table for open cursor where you could do a simple select
> statement:
> 
> DECLARE CURSOR FOO_CURSOR FOR SELECT * FROM MYTABLE;
> 
> SELECT _FIELD_NAME,_FIELD_TYPE,_FIELD_SIZE FROM
> FOO_CURSOR_INFO_PSEUTOTABLE;

The information you want is in pg_attribute.atttypmod.  It is normally
-1, but is set for char() and varchar() fields, and includes the 4-byte
length.  See bin/psql/psql.c for a sample of its use.

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