[SQL] add column if doesn't exist (fwd)

Started by Brandon Metcalfover 20 years ago3 messagesgeneral
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#1Brandon Metcalf
bmetcalf@nortel.com

I figured pgsql-general would be a more appropriate forum for the
question below.

--
Brandon

---------- Forwarded message ----------
Date: Mon, 26 Sep 2005 15:38:56 -0500 (CDT)
From: "Metcalf, Brandon [SC100:CM21:EXCH]" <bmetcalf@americasm01.nt.com>
To: pgsql-sql@postgresql.org
Subject: [SQL] add column if doesn't exist

Is there a way to check for the existence of a column in a table other
than, say, doing a SELECT on that column name and checking the output?

I'm basically looking to do an ALTER TABLE foo ADD COLUMN bar if bar
doesn't exist.

Thanks.

--
Brandon

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#2Qingqing Zhou
zhouqq@cs.toronto.edu
In reply to: Brandon Metcalf (#1)
Re: [SQL] add column if doesn't exist (fwd)

""Brandon Metcalf"" <bmetcalf@nortel.com> wrote

Is there a way to check for the existence of a column in a table other
than, say, doing a SELECT on that column name and checking the output?

Take a look at pg_attribute system table.
http://www.postgresql.org/docs/8.0/static/catalog-pg-attribute.html

Regards,
Qingqing

#3Jim Nasby
Jim.Nasby@BlueTreble.com
In reply to: Qingqing Zhou (#2)
Re: [SQL] add column if doesn't exist (fwd)

On Mon, Sep 26, 2005 at 07:16:53PM -0700, Qingqing Zhou wrote:

""Brandon Metcalf"" <bmetcalf@nortel.com> wrote

Is there a way to check for the existence of a column in a table other
than, say, doing a SELECT on that column name and checking the output?

Take a look at pg_attribute system table.
http://www.postgresql.org/docs/8.0/static/catalog-pg-attribute.html

You might find the information_schema or pg_newsysviews
(http://pgfoundry.org/projects/newsysviews/) easier to use.
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Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com
Pervasive Software http://pervasive.com work: 512-231-6117
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