Re: concenation of strings and null values

From: Greg Stark <gsstark(at)mit(dot)edu>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: concenation of strings and null values
Date: 2003-10-07 14:58:09
Message-ID: 87brstccxq.fsf@stark.dyndns.tv
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Tino Wildenhain <tino(at)wildenhain(dot)de> writes:

> So null (or none, or undefined ...) in most
> languages map to "" (Empty string)

Not in SQL. In SQL null means "unknown". If it's unknown then it's still
unknown when there's something attached to the beginning of it.

--
greg

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