sql语句嵌套更新

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sql语句嵌套更新

update b

set b.unitename='套'

from a,b

where a.id=b.id

and a.typeid=13

sql语句update语句中嵌套的子查询该怎么写？

UPDATE ccms_case_allot_count SET

org_code = BCTL.brno

,collector_name = INF.tlrno

FROM ccms_case_allot_count CO

LEFT JOIN sys_tlr_info INF ON CO.collector = inf.tlr_name

LEFT JOIN sys_bctl BCTL ON INF.brcode = BCTL.brcode

SQL 语句 UPDATE带嵌套子查询的问题

create table AAA( mc varchar(10), s1 int )

insert AAA values('A','997')

insert AAA values('B','1234')

create table BBB( mc varchar(10), s1 int )

insert BBB values('A','105')

insert BBB values('A','213')

insert BBB values('B','116')

insert BBB values('B','211')

insert BBB values('B','303')

-- 更新A表里S1值，A表里S1值-去B表里值

-- ? B表里S1值之合?

update AAA set

s1 = s1 - isnul((select sum(s1) from BBB where BBB.mc=AAA.mc),0)

-- next for M$SQL:

update AAA set

s1 = s1 - B.s1

from AAA

join (select mc, sum(s1) as s1 from BBB group by mc) B

on B.mc = AAA.mc

SQL中 update嵌套select怎么使用？

UPDATE A SET 时间 = ( SELECT MAX(时间) FROM B WHERE A.ID = B.ID )

求SQL语句 UPDATE嵌套select

UPDATE fastmanowner.FSys_FlowDef SET sFlowClass = '项目审批' WHERE sFlowClass != '项目审批'

标准SQL嵌套查询语句

在一个SELECT 语句的WHERE 子句或HAVING 子句中嵌套另一个SELECT 语句的查询称为嵌套查询，又称子查询。子查询是SQL 语句的扩展，例如下：

select * from table1 where xh in

(select xh from table2)

sql语句嵌套太深怎么修改

最外层的SQL SELECT语句里面的条件，你不要全部套进去，应该先把条件查出来，然后组建最外层SQL语句。简单来说，就是将里面的SELECT语句查出来的结果保存到变量中，然后再来将条件整合，组成最外层SQL语句。LEFT，它并不是加快查询速度，它只不过加快结果集返回的速度。实际上，你并不能感觉到这速度的提高。不过我们还是建议，当你查询很长字符串时（比如说记录的标题）在页面中显示，可以使用LEFT在SQL服务端进行字符截取。

sql 更新（update）语句嵌套问题

update [Membership] set Password=@password where Membership.UserId = (select Users.UserId from Users where UserName=@username)

将[Users]改为Users

请问SQL语句只可以进行一层嵌套吗？我想实现两层或以上的嵌套语句，但是嵌套后只符合其中一个嵌套条件

可以多个嵌套，但是只要一个条件不满足结果都查询不到，你把语句写出来看下

Update Table Set a='5' Where b=

(Select b

From Table

Where c In (Select c

From Dmpedi.Pps_Temp

Where b = '2'

And Rownum < 5)

And Rownum = 1)

sql中delete嵌套的问题

delete from posts_99 where authorid in (select authorid from posts_99 group by authorid having count(message)<3)

中select authorid from posts_99 group by authorid having count(message)<3

查询条件中没有count(message)，所以having条件不成立。

select authorid，count(message) from posts_99 group by authorid having count(message)<3 这样的查询才成立，但在delete语句中不适用。

用两步来解决

1。将查询结果放到一个临时表中

select authorid，count(message) SL into #a from posts_99 group by authorid having count(message)<3

2.关联临时表做delete

delete from posts_99 where authorid in (select authorid from #a)

sql语句嵌套更新