请问关于postgreSQL触发器？？？？

我想做一个，删除主键记录。后删除所有相关外建的记录。

CREATE OR REPLACE FUNCTION siteuser_delete (integer) RETURNS TRIGGER AS '
BEGIN
Delete from link where id = $1;
END;
' LANGUAGE 'plpgsql';

CREATE TRIGGER siteuser_trigger
BEFORE DELETE ON siteuser FOR EACH ROW
EXECUTE PROCEDURE siteuser_delete (NEW.id);

可以吗？？？
或

CREATE OR REPLACE FUNCTION siteuser_delete () RETURNS TRIGGER AS '
BEGIN
Delete from link where id = NEW.id;
END;
' LANGUAGE 'plpgsql';

CREATE TRIGGER siteuser_trigger
BEFORE DELETE ON siteuser FOR EACH ROW
EXECUTE PROCEDURE siteuser_delete ();
或可不可以象oracle 那样写
CREATE TRIGGER siteuser_trigger
BEFORE DELETE ON siteuser FOR EACH ROW
BEGIN
Delete from link where id = NEW.id;
END;