From: Daevid Vincent
Date: October 23 2007 1:04am
Subject: How to know the number of rows used in a SELECT MAX() query? FOUND_ROWS() not working.
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Is there a way to know how many rows were used in a computation? 

I tried this 'trick' but I still get 1, when I know that there are 3 rows
used...

SELECT SQL_CALC_FOUND_ROWS 
	MAX(DATE_ADD('2007-10-18 18:04:45', INTERVAL user_access_hours
HOUR)), 
	MAX(access_expire)
FROM
	end_user_groups 
	  JOIN end_user_group_links ON gid = id 
WHERE 
	enabled = 1 AND uid = 16;

select FOUND_ROWS();


<http://dev.mysql.com/doc/refman/5.0/en/select.html>
<http://dev.mysql.com/doc/refman/5.0/en/information-functions.html#function_
found-rows>