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Re: PRIMARY KEY on a *group* of columns imply that each column is NOT - Mailing list pgsql-general

From Stephane Bortzmeyer
Subject Re: PRIMARY KEY on a *group* of columns imply that each column is NOT
Date
Msg-id 20050427140632.GA29093@nic.fr
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In response to Re: PRIMARY KEY on a *group* of columns imply that each column is NOT  (ptjm@interlog.com (Patrick TJ McPhee))
Responses Re: PRIMARY KEY on a *group* of columns imply that each  (Scott Marlowe <smarlowe@g2switchworks.com>)
Re: PRIMARY KEY on a *group* of columns imply that each  (Scott Marlowe <smarlowe@g2switchworks.com>)
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On Wed, Apr 27, 2005 at 05:19:32AM +0000,
 Patrick TJ McPhee <ptjm@interlog.com> wrote
 a message of 37 lines which said:

> but you should know that in SQL, unique constraints don't apply to
> rows containing null values

May be I should but I didn't.

> your table definition will be as you want it, but the constraint you
> want won't be there.

OK, I will try to write a custom trigger, then.

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