Function op_error

src/backend/parser/parse_oper.c:633–657

* op_error - utility routine to complain about an unresolvable operator */

 * op_error - utility routine to complain about an unresolvable operator
 */
static void
op_error(ParseState *pstate, List *op, char oprkind,
		 Oid arg1, Oid arg2,
		 FuncDetailCode fdresult, int location)
{
	if (fdresult == FUNCDETAIL_MULTIPLE)
		ereport(ERROR,
				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
				 errmsg("operator is not unique: %s",
						op_signature_string(op, oprkind, arg1, arg2)),
				 errhint("Could not choose a best candidate operator. "
						 "You might need to add explicit type casts."),
				 parser_errposition(pstate, location)));
	else
		ereport(ERROR,
				(errcode(ERRCODE_UNDEFINED_FUNCTION),
				 errmsg("operator does not exist: %s",
						op_signature_string(op, oprkind, arg1, arg2)),
				 (!arg1 || !arg2) ?
				 errhint("No operator matches the given name and argument type. "
						 "You might need to add an explicit type cast.") :
				 errhint("No operator matches the given name and argument types. "
						 "You might need to add explicit type casts."),
				 parser_errposition(pstate, location)));
}

/*
 * make_op()