Oracle PL/SQL Tutorial/Collections/IS NULL

IS NULL operator checks whether a variable value is null

SQL>
SQL>  DECLARE
  2     var BOOLEAN;
  3    BEGIN
  4     IF var IS NULL THEN
  5      dbms_output.put_line("It is null.");
  6     END IF;
  7    END;
  8    /
It is null.
PL/SQL procedure successfully completed.
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