delimiter $$
CREATE FUNCTION lswlif(qian decimal(6,2))
RETURNS varchar(10) CHARSET utf8
BEGIN
if (qian > 0) then
  RETURN '亏';
elseif (qian < 0) then
  RETURN '盈';
ELSE
  RETURN '平';
end if;
END $$
delimiter ;

show function status;

DROP FUNCTION lswlif;