Re: The BOOLEAN data type

From: Tony <andrewst_at_onetel.net.uk>
Date: 30 Mar 2003 08:57:35 -0800
Message-ID: <c0e3f26e.0303300857.7356e336_at_posting.google.com>


"Troels Arvin" <troels_at_arvin.dk> wrote in message news:<pan.2003.03.30.03.23.09.939599_at_arvin.dk>...
> It strikes me as odd that the BOOLEAN data type is not a core requirement
> in SQL:1999 while so many other esoteric features are.

I agree. I've never known a database that didn't want BOOLEAN columns, but instead had to use CHAR(1) columns with names like ACTIVE_YN and (hopefully) a check constraint to ensure only 'Y' or 'N' got stored in it.

> Anyways:
> _When_ it's implemented, it's not clear to me which domain the type has.
> Are all the following values allowed?:
>
> true
> false
> unknown
> null
>
> Does null equal unknown?

null means unknown, so there is no need for a separate "unknown" value. Received on Sun Mar 30 2003 - 18:57:35 CEST

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