Oracle Message ORA-02471 - SYSDATE, UID, USER, ROWNUM, or LEVEL incorrectly used in hash expression.

ERROR	SYSDATE, UID, USER, ROWNUM, or LEVEL incorrectly used in hash expression.
CAUSE	SYSDATE, UID, USER, ROWNUM, or LEVEL are not allowed in hash expressions.
ACTION	Recreate the cluster and remove the offending keywords.