From: Forest Wilkinson <lyris-pg@tibit.com>
To: Rod Taylor <rbt@rbt.ca>
Cc: pgsql-sql@postgresql.org
Subject: Re: how to determine array size
Date: Tue, 10 Jun 2003 10:45:36 -0700
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	<1055246667.56597.39.camel@jester>
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>> I need to enumerate the constraints on any given column in a table, so
>> I'm examining pg_constraint to get the relevant information.  The
>> conkey array contains a list of constrained columns, and although I am
>> able to check conkey[1] for constraints on a single column, I would
>> like to properly handle multi-column constraints.
>
>You may have an easier time dealing with pg_get_constraintdef() than
>trying to get the info from the source.

Is pg_get_constraintdef() documented somewhere?  I'd like to know it's
arguments, return format, and whether it will be supported in future
postgres releases.

=46rom what I see in pg_dump.c, it appears to accept an oid from the
pg_constraint table, and only work with foreign key constraints.
True?  That might be useful in some special-case code, but I really
want a method that will work with all types of constraint.  (The idea
here is to enumerate all constraints on a table, along with their
names, types, and constrained columns.)