Oracle PL/SQL Tutorial/Collections/IS A SET

IS A SET Operator

You use the IS A SET operator to check if the elements in a nested table are distinct.

SQL> CREATE OR REPLACE PROCEDURE is_a_set_example AS
  2    TYPE nestedTableType IS TABLE OF VARCHAR2(10);
  3    myTable1 nestedTableType;
  4    result BOOLEAN;
  5  BEGIN
  6    myTable1 := nestedTableType("F", "G", "S", "G");
  7    result := myTable1 IS A SET;
  8    IF result THEN
  9      DBMS_OUTPUT.PUT_LINE("Elements are all unique");
 10    ELSE
 11      DBMS_OUTPUT.PUT_LINE("Elements contain duplicates");
 12    END IF;
 13  END is_a_set_example;
 14  /
Procedure created.
SQL> CALL is_a_set_example();
Elements contain duplicates
Call completed.
SQL>
SQL>