TRY/CATCH无法解决SQL Server代理错误？

Question

我sp_start_job用来开始工作.

job(test2)只有一步:

select getdate()
waitfor delay '00:00:10'

该TRY/CATCH代码:

begin try
    EXEC msdb.dbo.sp_start_job @job_name = 'test2'
end try
begin catch
    print 'error'
end catch

首次运行代码:

Job'test2'成功启动.

第二次运行代码(10秒内):

消息22022,级别16,状态1,行0
SQLServerAgent错误:请求运行作业test2(来自用户sa)被拒绝,因为作业已经从用户sa的请求运行.

为什么TRY/CATCH在这种情况下不起作用？

更新:我应该首先添加我正在使用链接服务器(sql server 2000)的sql server 2005.我试图在sql server 2005服务器上编写一个proc来查看所有链接服务器上的作业.如果作业未运行,请运行它.最初,我使用try-catch并希望在运行已经运行的作业时捕获任何错误但是失败了(这个线程).

我终于使用了以下代码:(它不会编译,你需要替换一些变量,只是给出一个想法)

    CREATE TABLE [dbo].[#jobInfo](
        [job_id] [uniqueidentifier] NULL,
        [originating_server] [nvarchar](30) ,
        [name] [nvarchar](128) ,
        [enabled] [tinyint] NULL,
        [description] [nvarchar](512) ,
        [start_step_id] [int] NULL,
        [category] [nvarchar](128) ,
        [owner] [nvarchar](128) ,
        [notify_level_eventlog] [int] NULL,
        [notify_level_email] [int] NULL,
        [notify_level_netsend] [int] NULL,
        [notify_level_page] [int] NULL,
        [notify_email_operator] [nvarchar](128) ,
        [notify_netsend_operator] [nvarchar](128) ,
        [notify_page_operator] [nvarchar](128) ,
        [delete_level] [int] NULL,
        [date_created] [datetime] NULL,
        [date_modified] [datetime] NULL,
        [version_number] [int] NULL,
        [last_run_date] [int] NOT NULL,
        [last_run_time] [int] NOT NULL,
        [last_run_outcome] [int] NOT NULL,
        [next_run_date] [int] NOT NULL,
        [next_run_time] [int] NOT NULL,
        [next_run_schedule_id] [int] NOT NULL,
        [current_execution_status] [int] NOT NULL,
        [current_execution_step] [nvarchar](128) ,
        [current_retry_attempt] [int] NOT NULL,
        [has_step] [int] NULL,
        [has_schedule] [int] NULL,
        [has_target] [int] NULL,
        [type] [int] NOT NULL
    )


    SET @sql = 
    'INSERT INTO #jobInfo
    SELECT * FROM OPENQUERY( [' + @srvName + '],''set fmtonly off exec msdb.dbo.sp_help_job'')'

    EXEC(@sql)

    IF EXISTS (select * from #jobInfo WHERE [name] = @jobName AND current_execution_status IN (4,5)) -- 4: idle, 5: suspended 
    BEGIN
        SET @sql = 'EXEC [' + @srvName + '].msdb.dbo.sp_start_job @job_name = ''' + @jobName + ''''
        --print @sql    
        EXEC (@sql) 
        INSERT INTO #result (srvName ,status ) VALUES (@srvName, 'Job started.')
    END ELSE BEGIN
        INSERT INTO #result (srvName ,status ) VALUES (@srvName, 'Job is running already. No action taken.')
    END

Answer 1

并非所有错误都可以被捕获TRY/CATCH.在这种情况下,sp_start_job实际上调用外部过程,这些超出了SQL Server的错误处理范围.或者至少那是他们坚持的故事:

http://connect.microsoft.com/SQLServer/feedback/details/362112/sp-start-job-error-handling

另请注意,这仍是SQL Server 2012 SP1 CU3中的问题.如果您想修复此错误,请投票和评论.

一个繁琐但可行的解决方法,需要某些权限,在这种情况下假定作业所有者是sa:

DECLARE @x TABLE
(
  a VARBINARY(32),b INT,c INT,d INT,e INT,f INT,g INT,h INT,i NVARCHAR(64),
  Running BIT, -- the only important column
  k INT,l INT,m INT
);

DECLARE @job_id UNIQUEIDENTIFIER;

SELECT @job_id = job_id FROM msdb.dbo.sysjobs WHERE name = N'test2';

INSERT @x EXEC master.dbo.xp_sqlagent_enum_jobs 1, N'sa', @job_id;

IF EXISTS (SELECT 1 FROM @x WHERE Running = 0)
BEGIN
     EXEC msdb.dbo.sp_start_job @job_name = N'test2';
END
ELSE
BEGIN
     PRINT 'error';
END

更好的可能是:

DECLARE @job_id UNIQUEIDENTIFIER, @d DATETIME;

SELECT @job_id = job_id FROM msdb.dbo.sysjobs WHERE name = N'test2';

SELECT @d = stop_execution_date 
  FROM msdb.dbo.sysjobactivity WHERE job_id = @job_id;

IF @d IS NOT NULL
BEGIN
     EXEC msdb.dbo.sp_start_job @job_name = N'test2';
END
ELSE
BEGIN
     PRINT 'error';
END

在任何一种情况下,仍然可能在检查其状态和启动它的调用之间开始作业,因此这并不能sp_start_job完全消除错误,但这使得它们不太可能发生.