CREATE OPERATOR

Descripción: Defines a new user operator

CREATE OPERATOR name ( PROCEDURE = func_name
     [, LEFTARG = type1 ] [, RIGHTARG = type2 ]
     [, COMMUTATOR = com_op ] [, NEGATOR = neg_op ]
     [, RESTRICT = res_proc ] [, JOIN = join_proc ]
     [, HASHES ] [, SORT1 = left_sort_op ] [, SORT2 = right_sort_op ] )