使用RETURNS void如下：
原文链接：https://www.f2er.com/postgresql/193418.htmlCREATE FUNCTION stamp_user(id int,comment text) RETURNS void AS $$
#variable_conflict use_variable
DECLARE
curtime timestamp := now();
BEGIN
UPDATE users SET last_modified = curtime,comment = comment
WHERE users.id = id;
END;
$$ LANGUAGE plpgsql;
