T-SQL 事务2

启用事务完成转账存储过程

 use StudentManager
 go
 if exists(select * from sysobjects where name='usp_TransferAccounts')
 drop procedure usp_TransferAccounts
 go
 create procedure usp_TransferAccounts
 @inputAccount int,--转入账户
 @outputAccount int,--转出账户
 @transferMoney int --交易金额
 as
     declare @errorSum int
     set @errorSum=0
     begin transaction
        begin
             update CardAccount set CurrentMoney=CurrentMoney-@transferMoney
                         where StudentId=@outputAccount
             set @errorSum=@errorSum+@@error
             update CardAccount set CurrentMoney=CurrentMoney+@transferMoney
                         where StudentId=@inputAccount
            set @errorSum=@errorSum+@@error
            if(@errorSum>0)
                 rollback transaction
            else
                 commit transaction
      end
 go
 --测试失败的转账
 exec usp_TransferAccounts 100002,100001,1000
 --查询余额
 select Students.StudentId,StudentName,CurrentMoney from Students
 inner join CardAccount on Students.StudentId=CardAccount.StudentId
 --测试成功的转账
 exec usp_TransferAccounts 100002,100001,800
 --查询余额
 select Students.StudentId,StudentName,CurrentMoney from Students
 inner join CardAccount on Students.StudentId=CardAccount.StudentId