The statement contains a call on an aggregate function within the parameter list for another aggregate function, such as SUM(MAX(column)). This action is not supported because all aggregates are calculated over the same groups of rows. If you did not intend an expression of this sort, look for missing or misplaced parentheses. If you did intend it, rethink the query. For example, you might select the MAX values into a temporary table and then take their SUM.