This SELECT statement selects one or more BYTE or TEXT values and also specifies those columns in the GROUP BY clause. This action is not supported. Since no defined lexical order to BYTE or TEXT values exists, the database server cannot order or compare them. Therefore it cannot group rows on their values. (This condition is true even of substrings selected from a BYTE or TEXT column.) Review your SELECT statement to ensure that the correct columns are named in the GROUP BY clause.