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Message-ID: <3932A73C.6FF32AAB@ec.gc.ca>
Date: Mon, 29 May 2000 10:22:05 -0700
From: Bernie Huang <bernie.huang@ec.gc.ca>
Organization: Environment Canada
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To: PGSQL-SQL <pgsql-sql@postgresql.org>
Subject: constraint
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Hi,

I am a newbie to SQL.  Could someone please explain why do I need a
contraint, and how do I use it in SQL?  An example is needed.  Thanks

- Bernie

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