From: Curt W. Zirzow Date: March 24 1999 8:04pm Subject: Query performance with functions List-Archive: http://lists.mysql.com/mysql/937 Message-Id: <19990324200452.8427.qmail@modgud.nordicdms.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Hello, I noticed that in the latest version of mysql that you no longer can use the column alias inside the where clause. Does this (ie. In the following query) cause the function be called in both cases or would it be called once and aliased in the where clause? select function(column) as column_alias from table where function(column) > 0 Curt.