END

ELSE CASE

     WHEN P2 >= P3

     THEN CASE

          WHEN P2 >= P4

          THEN CASE

               WHEN P2 >= P5 THEN P2

               ELSE               P5

               END

          ELSE CASE

               WHEN P4 >= P5 THEN P4

               ELSE               P5

               END

          END

     ELSE CASE

          WHEN P3 >= P4

          THEN CASE

               WHEN P3 >= P5 THEN P3

               ELSE               P5

               END

          ELSE CASE

               WHEN P4 >= P5 THEN P4

               ELSE               P5

               END

          END

     END

END

;

   GREATEST function with six parameters

CREATE FUNCTION GREATEST (P1 VarChar(254), P2 VarChar(254), P3 VarChar(254), P4 

VarChar(254)

                        , P5 VarChar(254), P6 VarChar(254))

 RETURNS VarChar(254)

 LANGUAGE SQL

 SPECIFIC GREATESTOracle6

 DETERMINISTIC

 CONTAINS SQL

 NO EXTERNAL ACTION

 RETURN 

GREATEST(GREATEST(P1,P2,P3),GREATEST(P4,P5,P6))

;

   GREATEST function with seven parameters

 Appendix A. Sample code for user defined functions 

349