当没有用 EXISTS 引入子查询时，在选择列表中只能指定一个表达式

2010-10-21 02:14:21 2.1k 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

安卓无障碍服务保活实战：如何用AccessibilityService实现后台常驻（附完整代码）本文深入解析如何利用Android无障碍服务（AccessibilityService）实现后台服务保活，涵盖多版本系统适配、前台服务集成、开机自启机制等关键技术。通过详细的Kotlin代码示例和合规性指导，帮助开发者构建稳定可靠的后台服务解决方案，同时避免因滥用无障碍服务导致的应用下架风险。阅读详情



if exists(select * from sysobjects where name='Result' )

 drop table Result



select LineNum as 线路,SIM as 号码 into Result  from UV_MsgInbox t1 

where t1.MsgArrivedTime >= dateadd(minute,-5,getdate())

	 and MsgTitle='外接电源断电，启动内置电源' 

	          and not exists(select * from UV_MsgInbox t2

                      where t2.Sender = t1.SIM

                       and t2.MsgArrivedTime >= dateadd(minute,-5,getdate())

                       and t2.MsgTitle ='恢复正常供电')

  group by  t1.SIM,t1.LineNum 

select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2



if exists(select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2)

  begin





	declare @receiver varchar(500)

	set @receiver='13737740287,15878359061,15812405921'

	if exists (select * from UV_MsgInbox t1 where  t1.MsgType=1 and t1.MsgArrivedTime >= dateadd(minute,-5,getdate())  

			and t1.sender in (select 号码  from Result group by 号码 having count(DISTINCT 号码)>=2))--后半括号中子查询不对

子查询想要的是select 线路，号码 from Result group by 线路，号码 having count(DISTINCT 号码)>=2这条sql执行结果中的号码

怎么写才对呢

...全文

从2-RSS-1U并联踝关节到双足机器人动态行走：雅可比矩阵与力矩控制实践本文深入探讨了2-RSS-1U并联踝关节在双足机器人动态行走中的关键作用，详细解析了其设计原理、雅可比矩阵的应用及力矩控制实践。通过优化几何参数和控制算法，实现了低转动惯量、高刚度和紧凑设计，显著提升了机器人的行走稳定性和能量效率。文章还分享了从仿真到实物的跨越经验及未来优化方向。阅读详情

mms89757

疑难问题 22,298 成员 121,727 内容

+ 关注 + 加入社区

切换为时间正序

mms89757 2010-10-21

打赏
举报



if exists(select * from sysobjects where name='Result' )

  drop table Result



select LineNum as 线路,SIM as 号码 into Result  from UV_MsgInbox t1 where t1.MsgArrivedTime >= dateadd(minute,-5,getdate()) and MsgTitle='外接电源断电，启动内置电源'  and not exists(select * from UV_MsgInbox t2 where t2.Sender = t1.SIM

 	and t2.MsgArrivedTime >= dateadd(minute,-5,getdate())

     and t2.MsgTitle ='恢复正常供电')

    group by  t1.SIM,t1.LineNum 

select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2

      if exists(select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2)

  	begin

	--declare @receiver varchar(500)

	--set @receiver='13737740287,15878359061,15812405921'

	 if exists (select * from UV_MsgInbox t3 where  t3.MsgType=1 and t3.MsgArrivedTime >= dateadd(minute,-5,getdate())  and t3.sender in (select 号码 from Result group by 号码))--后半括号中子查询不对

	    begin

               ......后面省略

这样写行不？

mms89757 2010-10-21

打赏
举报

错了，错了。。。
后面还要判断号码个数是否大于等于2
就像这句select 线路 from Result group by 线路 having count(DISTINCT 号码)>=2这样
上面的子查询还没判断，能够在上面的基础上加上判断号码这个条件就是最后要的结果了

mms89757 2010-10-21

打赏
举报



if exists(select * from sysobjects where name='Result' )

  drop table Result



select LineNum as 线路,SIM as 号码 into Result  from UV_MsgInbox t1 where t1.MsgArrivedTime >= dateadd(minute,-5,getdate()) and MsgTitle='外接电源断电，启动内置电源'  and not exists(select * from UV_MsgInbox t2 where t2.Sender = t1.SIM

 	and t2.MsgArrivedTime >= dateadd(minute,-5,getdate())

     and t2.MsgTitle ='恢复正常供电')

    group by  t1.SIM,t1.LineNum 

select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2

      if exists(select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2)

  	begin

	--declare @receiver varchar(500)

	--set @receiver='13737740287,15878359061,15812405921'

	 if exists (select * from UV_MsgInbox t3 where  t3.MsgType=1 and t3.MsgArrivedTime >= dateadd(minute,-5,getdate())  and t3.sender in (select SIM as 号码 from UV_MsgInbox t1 where t1.MsgArrivedTime >= dateadd(minute,-5,getdate())

			 and MsgTitle='外接电源断电，启动内置电源' 

	             and not exists(select * from UV_MsgInbox t2

                      where t2.Sender = t1.SIM

                       and t2.MsgArrivedTime >= dateadd(minute,-5,getdate())

                       and t2.MsgTitle ='恢复正常供电')

  			group by  t1.SIM,t1.LineNum ))--后半括号中子查询不对

	    begin

                 ......下面内容省略

这样写的话就是我要的结果，但是这些语句太长太繁琐，所以看看能不能简化它让人看起来不那么头疼

SQLCenter 2010-10-21

打赏
举报

[Quote=引用 4 楼 mms89757 的回复:]
这个好像不行。我数据里面明明存在有符合条件的号码，这样写的话查询的时候查询结果是空的
[/Quote]
那不是这条语句的问题，看看其他方面的逻辑，这条语句能找到你预期的“号码”

mms89757 2010-10-21

打赏
举报

[Quote=引用 2 楼 sqlcenter 的回复:]
这样不就行了吗，你要什么列随你啊，反正在 group by 列表就行：

select 号码 from Result group by 线路，号码 having count(DISTINCT 号码)>=2
[/Quote]
这个好像不行。我数据里面明明存在有符合条件的号码，这样写的话查询的时候查询结果是空的

abuying 2010-10-21

打赏
举报



if exists (select * from UV_MsgInbox t1 where  t1.MsgType=1 and t1.MsgArrivedTime >= dateadd(minute,-5,getdate())  

            and exists (select 号码  from Result where t.sender=result.号码 group by 号码 having count(DISTINCT 号码)>=2))

SQLCenter 2010-10-21

打赏
举报

这样不就行了吗，你要什么列随你啊，反正在 group by 列表就行：

select 号码 from Result group by 线路，号码 having count(DISTINCT 号码)>=2

claro 2010-10-21

打赏
举报

if exists(select 线路  from Result  group by 线路 having count(DISTINCT 号码)>=2)

begin

declare @receiver varchar(500)

set @receiver='13737740287,15878359061,15812405921'

if exists (select * from UV_MsgInbox t1 where  t1.MsgType=1 and t1.MsgArrivedTime >= dateadd(minute,-5,getdate() 

 and t1.sender in (select 号码  from Result group by 号码 having count(DISTINCT 号码)>=2))

真没看懂，不过if判断好像多了个）

当没有用 EXISTS 引入子查询时，在选择列表中只能指定一个表达式

相关推荐