>> In real application I have long expression instead of 123 and do'nt want >> repeat this expression in HAVING clause. > > You have to repeat the expression. "AS" changes the output name, it > can't be used either in the where clause or any other limiting factor > like 'having': Doc about HAVING condition says: Each column referenced in condition must unambiguously reference a grouping colum HAVING x> AVG(bar) unambiguously references to a grouping column x Is this bug ? It is very tedious to repeat same column expression in a multiple times: one time in column expression, and n times in having clause. Are there plans to fix this? Andrus.