当对多个表进行更新的时候,某条执行失败。为了保持数据的完整性,需要使用事务回滚
为什么使用事务当对多个表进行更新的时候,某条执行失败。为了保持数据的完整性,需要使用事务回滚。
显示设置事务
代码如下:
begin try
begin transaction
insert into shiwu (asd) values ('aasdasda');
commit transaction
end try
begin catch
select ERROR_NUMBER() as errornumber
rollback transaction
end catch
隐式设置事务
代码如下:
set implicit_transactions on; -- 启动隐式事务
go
begin try
insert into shiwu (asd) values ('aasdasda');
insert into shiwu (asd) values ('aasdasda');
commit transaction;
end try
begin catch
select ERROR_NUMBER() as errornumber
rollback transaction; --回滚事务
end catch
set implicit_transactions off; --关闭隐式事务
go
显示事务以下语句不能使用,隐式事务可以
代码如下:
alter database;
backup;
create database;
drop database;
reconfigure;
restore;
update statistics;
显示事务可以嵌套使用
代码如下:
--创建存储过程
create procedure qiantaoProc
@asd nchar(10)
as
begin
begin try
begin transaction innerTrans
save transaction savepoint --创建事务保存点
insert into shiwu (asd) values (@asd);
commit transaction innerTrans
end try
begin catch
rollback transaction savepoint --回滚到保存点
commit transaction innerTrans
end catch
end
go
begin transaction outrans
exec qiantaoProc 'asdasd';
rollback transaction outrans
事务嵌套,回滚外层事务时,如果嵌套内的事务已经回滚过则会有异常。此时需要使用事务保存点。如上代码。

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