fyqt.net
当前位置:首页 >> sql 关联删除 >>

sql 关联删除

删除多表关联数据的三种方法1、级联删除 create table a(id varchar(20) primary key,password varchar(20) not null)create table b(id int identity(1,1) primary key,name varchar(50) not null,userId varchar(20),foreign key (userId) ref...

delete from tableA where 关联键 in(select 外键 from tableB where bookID=1) delete from tableB where bookid= 1 只能一个个删除,你先删除主表,条件为查出来的。再删子表。(如果没有级联设置)

SQL 关键字 delete ,inner join 假如定义A表,有字段a,b ,类型都为int B 表有字段b,c 类型都为int 下列是关联查询SQL 如下: select * from A inner join B on A.b=B.b 删除SQL 语句: delete from A where a in (select A.a from A inner j...

删除主-从表的记录可以建立简单存储过程来实现: CREATE PROCEDURE [存储过程] ( @Id VARCHAR(50) ) AS DELETE [子表] WHERE [关联Id] = @Id DELETE [主表] WHERE [Id] = @Id GO 执行方法:EXECUTE [存储过程] @Id

删除主-从表的记录可以建立简单存储过程来实现: CREATE PROCEDURE [存储过程] ( @Id VARCHAR(50) ) AS DELETE [子表] WHERE [关联Id] = @Id DELETE [主表] WHERE [Id] = @Id GO 执行方法:EXECUTE [存储过程] @Id

那就删除两个表之间的外键就可以。 如下图的表: 可查询出: select name from sys.foreign_key_columns f join sys.objects o on f.constraint_object_id=o.object_id where f.parent_object_id=object_id('表名') 删除的一般语法为: alter ta...

可以使用两种方式 1:删除子表数据,再删除主表数据 2:如果主细表中建立了级联删除操作,直接删除主表数据即可

delete from B where id in (select A.id from A, B where A.身份证号码=B.身份证号码 并且 A.金额=B.金额 )

delete from specification where uid in (select id from user where datediif(d,timessb,getdate())>30) delete from user where datediif(d,timessb,getdate())>30

一个sql语句是没办法执行两个删除操作,如果你要实现上面的功能,有以下几个选择: 1.用外键关联删除,把B表的uid设成外键关联A表的ID,并关联删除操作 2.用存储过程,用事务来处理实现; 望采纳!

网站首页 | 网站地图
All rights reserved Powered by www.fyqt.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com