请问 ORA-01427: 单行子查询返回多个行 这个错误是如何解决呢？
以下语句执行后报 ORA-01427: 单行子查询返回多个行 这个错误，请问是怎么解决呢？多谢
update IRPT_DEPARTMENTS a
  set a.FZJG=
  (
  select wt1_1.C48
  from WSXXZB.WT1_1NB_B1 wt1_1
  where wt1_1.Userid_=a.id and wt1_1.bbq_='2007----'
  union all
  select wt1_2.C27
  from WSXXZB.WT1_2NB_B1 wt1_2
  where wt1_2.Userid_=a.id and wt1_2.bbq_='2007----'
  union all
  select wt1_6.C23
  from WSXXZB.WT1_6NB_B1 wt1_6
  where wt1_6.Userid_=a.id and wt1_6.bbq_='2007----'
  union all
  select wt1_7.C28
  from WSXXZB.WT1_7NB_B1 wt1_7
  where wt1_7.Userid_=a.id and wt1_7.bbq_='2007----'
  union all
  select wt1_8.C22
  from WSXXZB.WT1_8NB_B1 wt1_8
  where wt1_8.Userid_=a.id and wt1_8.bbq_='2007----'
  )
where exists
  (
  select 1
  from WSXXZB.WT1_1NB_B1 wt1_1
  where wt1_1.Userid_=a.id and wt1_1.bbq_='2007----'
  union all
  select 1
  from WSXXZB.WT1_2NB_B1 wt1_2
  where wt1_2.Userid_=a.id and wt1_2.bbq_='2007----'
  union all
  select 1
  from WSXXZB.WT1_6NB_B1 wt1_6
  where wt1_6.Userid_=a.id and wt1_6.bbq_='2007----'
  union all
  select 1
  from WSXXZB.WT1_7NB_B1 wt1_7
  where wt1_7.Userid_=a.id and wt1_7.bbq_='2007----'
  union all
  select 1
  from WSXXZB.WT1_8NB_B1 wt1_8
  where wt1_8.Userid_=a.id and wt1_8.bbq_='2007----'
  );

------解决方案--------------------
你返回了一个结果集。
set后面跟的只能是具体的数据。

增加查询条件。
具体解决方法由于不知道你想干什么。回答不上。
------解决方案--------------------
set a.FZJG= 
( 
select wt1_1.C48 
from WSXXZB.WT1_1NB_B1 wt1_1 
where wt1_1.Userid_=a.id and wt1_1.bbq_='2007----' 
union all 
select wt1_2.C27 
from WSXXZB.WT1_2NB_B1 wt1_2 
where wt1_2.Userid_=a.id and wt1_2.bbq_='2007----' 
union all 
select wt1_6.C23 
from WSXXZB.WT1_6NB_B1 wt1_6 
where wt1_6.Userid_=a.id and wt1_6.bbq_='2007----' 
union all 
select wt1_7.C28 
from WSXXZB.WT1_7NB_B1 wt1_7 
where wt1_7.Userid_=a.id and wt1_7.bbq_='2007----' 
union all 
select wt1_8.C22 
from WSXXZB.WT1_8NB_B1 wt1_8 
where wt1_8.Userid_=a.id and wt1_8.bbq_='2007----' 
) 

这段里面的select出现多行数据了
每行更新字段只能对应一个更新内容啊
------解决方案--------------------
像 二楼说的，把条件追加上，set 只能一对一。你的SQL好比是：

update tablename1 a set a.id=(select b.id from tablename2 b)
------解决方案--------------------

SQL code

试试:
UPDATE IRPT_DEPARTMENTS A
   SET A.FZJG = (SELECT WT1_1.C48
                   FROM WSXXZB.WT1_1NB_B1 WT1_1
                  WHERE WT1_1.USERID_ = A.ID
                    AND WT1_1.BBQ_ = '2007----'
                 UNION ALL
                 SELECT WT1_2.C27
                   FROM WSXXZB.WT1_2NB_B1 WT1_2
                  WHERE WT1_2.USERID_ = A.ID
                    AND WT1_2.BBQ_ = '2007----'
                 UNION ALL
                 SELECT WT1_6.C23
                   FROM WSXXZB.WT1_6NB_B1 WT1_6