Question

如果Notes表中不存在某个元素，那么之前的插入行应该回滚。我想通过将两行放在Begin事务中，它会回滚，但由于没有抛出错误，它会执行insert命令。如果不存在元素，如何抛出错误，以便回滚整个代码块？

begin try
    begin transaction
        insert into notes (memberid, NoteEffDate, LoginName, NoteDesc) values (367737, GETDATE(), 'marc', 'blah blah')
        IF EXISTS (SELECT memberid FROM notes WHERE memberid =4774769)
        begin
        update notes set notedesc = 'hello there' where memberid = 4774769
        end
    commit transaction
    end try
    begin catch
        rollback transaction
        select ERROR_MESSAGE()

        end catch
        go

Answer 1

您似乎正在尝试使用某些版本的Sam Saffron's upsert method。

程序的粗略版本：

create procedure dbo.notes_upsert (
    @memberid int
  , @notesdesc varchar(256)
  , @loginname varchar(256)
  ) as 
begin
  set nocount on;
  set xact_abort on;
  begin tran
    update notes (with serializable)
      set   notedesc = @notedesc
      where memberid = @memberid;
    if @@rowcount = 0
    begin;
      insert into notes (memberid, NoteEffDate, LoginName, NoteDesc) 
      values (@memberid, getdate(), @loginname, @notesdesc);
    end;
  commit tran
end;

Answer 2

您可能尝试阻止中的RaiseError。

begin try
begin transaction
    insert into notes (memberid, NoteEffDate, LoginName, NoteDesc) values (367737, GETDATE(), 'marc', 'blah blah')
    IF EXISTS (SELECT memberid FROM notes WHERE memberid =4774769)
    begin
    update notes set notedesc = 'hello there' where memberid = 4774769
    end
    ELSE 

-- RAISERROR with severity 11-19 will cause execution to   
-- jump to the CATCH block.  
RAISERROR ('Error raised in TRY block.', -- Message text.  
           16, -- Severity.  
           1 -- State.  
           ); 
commit transaction
end try
begin catch
    rollback transaction
    select ERROR_MESSAGE()

    end catch
    go

包含存在于开始事务中

2 个答案: