From: Martijn Tonies
Date: August 31 2004 12:40pm
Subject: Re: Concat
List-Archive: http://lists.mysql.com/mysql/171828
Message-Id: <001301c48f57$b90d7490$0a02a8c0@martijn>
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> Concat() returns Null if any field in the field list
> is Null.  How can I use it to return a String
> regardless, or is there another function to do it?

COALESCE(value,...)
Returns the first non-NULL value in the list.
mysql> SELECT COALESCE(NULL,1);
        -> 1
mysql> SELECT COALESCE(NULL,NULL,NULL);
        -> NULL
COALESCE() was added in MySQL 3.23.3.

So, if you use CONCAT(COALESCE(Myfield, ''), COALESCE(OtherField, '') )

With regards,

Martijn Tonies
Database Workbench - developer tool for InterBase, Firebird, MySQL & MS SQL
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