Message-ID: <3E3DAF01.8030006@klaster.net>
Date: Mon, 03 Feb 2003 00:51:29 +0100
From: Tomasz Myrta <jasiek@klaster.net>
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To: Agnieszka Rutkowska <agr225@cse.unsw.EDU.AU>
Cc: pgsql-sql@postgresql.org
Subject: Re: extracting constraints from schema
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 <Pine.LNX.4.44.0301291520380.16179-100000@piano07.orchestra.cse.unsw.EDU.AU>
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Agnieszka Rutkowska wrote:
> Hi,
> 
> I was just wondering whether you happen to know how to extract what the
> table and column constraints are using jdbc?
> The API provides methods for extracting meta data on the table names,
> column names, primary and foreigh keys as well as column types and sizes.
> What about extracting constraints such as
> 
> salary	real	CHECK (salary >= 10000)
> 
> ?
> It is possible to obtain the column name 'salary' as well as its types as
> being 'real' but how about the CHECK condition?? Can it be done using
> jdbc?
> 
> Thanks for your time and help
> Agnes

Did you try to extract any information from system table pg_constraint?
contype='C' is a CHECK condition. I think you can parse some additional
information from column consrc. Description of all columns in this table
is in "Chapter 3. System Catalogs 10. pg_constraint" at Postgresql documentation.

Regards,
Tomasz Myrta