您好,运行以下语句出现提示:错误ORA-01427:single-row subquery returns more than one row 麻烦检查并给予指正问题出在哪儿? select (case p.buytype when '002' then (select a.cweight as cw from cargoods a) when '001' then (select r.buyamount as buy from RAILSAMOUNT r) end) from puynote p where p.planno='UU20013' |