SQL 查询 "Subquery returned more than 1 value"

Question

我已经尝试修改来自应用程序的 SQL 查询，但无法使其正常工作

错误：

"Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression."

原查询：

SELECT fycode, fyname, class3, '', '', '', defje, zjm, '', ''
FROM zy_fy

UNION ALL
SELECT Ypcode, Ypname,
    (SELECT a.lbname FROM YK_yplb a where a.lbid = b.yplb)
, gg, sldw, '', '', '', '', ''
FROM YK_ypzd b

UNION ALL
SELECT FYID, NAME, DYKS+'-'+CLASS2, '', '次', '', FYMONEY, ZJM, ZJM1, '' 
FROM mz_fy

修改后的查询：

SELECT fycode, fyname, class3, '', '', '', defje, zjm, '', ''
FROM zy_fy

UNION ALL
SELECT Ypcode, Ypname, 
(select a.lbname from YK_yplb a  where a.lbid = b.yplb)
,gg,sldw, '', 
(select c.dj from YK_kc c  where c.Ypcode = b.Ypcode)
 ,'','',''
FROM YK_ypzd b

UNION ALL
SELECT FYID, NAME, DYKS+'-'+CLASS2, '', '次', '', FYMONEY, ZJM, ZJM1, ''
FROM mz_fy

我刚刚在第 3 个 select 语句的第 7 列中插入了一个子查询

谢谢！

Answer 1

    select fycode,fyname,class3,'','','',defje,zjm,'',''  from zy_fy union all
select  Ypcode, Ypname,(select a.lbname from YK_yplb a  where a.lbid =
b.yplb limit 1),gg,sldw,'',(select c.dj from YK_kc c  where c.Ypcode =
b.Ypcode),'','',''  from YK_ypzd b  union all  select FYID,NAME,DYKS+'-
+CLASS2,'','次','',FYMONEY,ZJM,ZJM1,''  from mz_fy

使用限制

Answer 2

你只需要使用TOP 1将子查询限制为return只有一行

SELECT fycode, fyname, class3, '', '', '', defje, zjm, '', ''
FROM zy_fy

UNION ALL
SELECT Ypcode, Ypname, 
(select TOP 1 a.lbname from YK_yplb a  where a.lbid = b.yplb)
,gg,sldw, '', 
(select TOP 1 c.dj from YK_kc c  where c.Ypcode = b.Ypcode)
 ,'','',''
FROM YK_ypzd b

UNION ALL
SELECT FYID, NAME, DYKS+'-'+CLASS2, '', '次', '', FYMONEY, ZJM, ZJM1, ''
FROM mz_fy

Answer 3

请使用TOP 1将子查询限制为return只有一行

SQL 查询 "Subquery returned more than 1 value"

SQL QUERY "Subquery returned more than 1 value"

sql

sql-server-2000