select (case when ACTIONTYPE='更新' then (select GUISHUZUZHI from table_name where FORM_NO=192) else (select AFTERUPZUZHI from table_name where FORM_NO=192) end) as '更新后组织'  from table_name where FORM_NO=192

select (case when ACTIONTYPE='更新' then 1 else 0 end) as '更新后组织'  from table_name where FORM_NO=192

select (case when ACTIONTYPE='更新' then GUISHUZUZHI else AFTERUPZUZHI end) as '更新后组织'  
from table_name where FORM_NO=192

------解决方案--------------------
我有一张表 表中有三个字段 a,b,c当c字段等于某个值时 查询得到 a字段的值 其他情况就查询到b字段的值
  下面有一个例子（报错）：

--

select * from tb where (c = '某个值' and a = ...) or (c <> '某个值' and b = ... )

------解决方案--------------------
select (case  when a.GiftType='1' then (select GiftName from tablename where GiftId=a.GiftId)  
else (select GiftId from tablename where GiftId=a.GiftId)  end) aaa  from tablename a where a.GiftId='001'