Swift项目进口框架，Xcode(Import Framework in Swift Project, Xcode)

 忽略安装位，您的脚本： 
 
 
 
 开始交易 
 
 
 删除 
 
 
 插入 
 
 
 运行一些生成错误的代码 
 
 
 做一个COMMIT 
 
 
 因此，当然这些初步变化已经应用。 您可以设置XACT_ABORT ，这将导致生成错误的任何批处理回滚事务，但您仍需要非常小心： 
 
create table T(ID int)
go
set xact_abort on
go
begin transaction
go
insert into T(ID) values (1)
go
alter table T add ID int null
go
insert into T(ID) values (2)
go
commit
go
select * from T
 
 生成以下消息： 
 
(1 row(s) affected)
Msg 2705, Level 16, State 4, Line 1
Column names in each table must be unique. Column name 'ID' in table 'T'
is specified more than once.

(1 row(s) affected)
Msg 3902, Level 16, State 1, Line 1
The COMMIT TRANSACTION request has no corresponding BEGIN TRANSACTION.

(1 row(s) affected)
 
 并且表中仍然有一行包含2 。 为什么？ 因为错误通过回滚终止了事务，但是下一批（包含insert into T(ID) values (2) ）运行时没有显式事务存在。 除了一些手动步骤之外， 在批量处理错误处理方面没有太多帮助，例如： 
 
create table T(ID int)
go
set xact_abort on
go
begin transaction
go
insert into T(ID) values (1)
go
alter table T add ID int null
go
if @@TRANCOUNT = 0 goto errored
insert into T(ID) values (2)
errored:
go
if @@TRANCOUNT = 0 goto errored
commit
errored:
go
select * from T
 
 并且您必须在每个包含错误的批次中执行相同的操作。 

Ignoring the setup bit, your script:
 
 
 
starts a transaction
 
 
does a delete
 
 
does an insert
 
 
runs a bit of code that generates an error
 
 
does a COMMIT
 
 
So, of course those initial changes have applied. You can set XACT_ABORT on which will cause any batch that generates an error to rollback the transaction, but you still need to be very careful:
 
create table T(ID int)
go
set xact_abort on
go
begin transaction
go
insert into T(ID) values (1)
go
alter table T add ID int null
go
insert into T(ID) values (2)
go
commit
go
select * from T
 
Produces these messages:
 
(1 row(s) affected)
Msg 2705, Level 16, State 4, Line 1
Column names in each table must be unique. Column name 'ID' in table 'T'
is specified more than once.

(1 row(s) affected)
Msg 3902, Level 16, State 1, Line 1
The COMMIT TRANSACTION request has no corresponding BEGIN TRANSACTION.

(1 row(s) affected)
 
And still has a row containing 2 in the table. Why? Because the error terminated the transaction with a rollback, but then the next batch (containing insert into T(ID) values (2)) was run without an explicit transaction existing. There's not much help you can get when it comes to error handling across batches, except some manual steps, e.g.:
 
create table T(ID int)
go
set xact_abort on
go
begin transaction
go
insert into T(ID) values (1)
go
alter table T add ID int null
go
if @@TRANCOUNT = 0 goto errored
insert into T(ID) values (2)
errored:
go
if @@TRANCOUNT = 0 goto errored
commit
errored:
go
select * from T
 
And you'll have to do the same in every batch that might follow one containing errors.