From: | Richard Huxton <dev(at)archonet(dot)com> |
---|---|
To: | Huub <v(dot)niekerk(at)freeler(dot)nl>, pgsql-general(at)postgresql(dot)org |
Subject: | Re: primary key question |
Date: | 2002-11-07 10:19:57 |
Message-ID: | 200211071019.58381.dev@archonet.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
On Thursday 07 Nov 2002 6:57 am, Huub wrote:
> Hi,
>
> Reading the online manual it doesn't get clear to me: can I or can't I
> define a primary key containing 2 columns, e.g. like:
>
> create table <name> (column1 char(10) not null, column2 char(20) not
> null, primary key (column1, column2))
Yes you can. The place to check this sort of information is in the SQL
Commands reference section of the manuals.
From CREATE TABLE:
"The primary key constraint specifies that a column or columns of a table may
contain only unique (non-duplicate), non-NULL values. "
You might also find the functional and partial indexing features of interest.
--
Richard Huxton
From | Date | Subject | |
---|---|---|---|
Next Message | Oskar Berggren | 2002-11-07 14:13:00 | Re: Q! |
Previous Message | Hervé Piedvache | 2002-11-07 09:38:18 | Failed to initialize lc_messages 7.3b5 |