rollec2k5 (1/21/2011)
I was not aware about, that you can use Columns in a having Clause without having the Column in the SELCET.
Not exactly.... The HAVING clause can use aggregates like COUNT(), MAX(), SUM() and so on which themselves refer to other columns, but it may not directly refer to a column not in the GROUP BY clause which in turn can only use columns or non-aggregate expressions in the SELECT.