SQL SERVER 2005删除维护作业报错：The DELETE statement conflicted with the REFERENCE constraint "FK_subplan_job_id"

案例环境：

    数据库版本： Microsoft SQL Server 2005 (Microsoft SQL Server 2005 - 9.00.5000.00 (X64) )

案例介绍：

    对一个数据库实例做清理工作时，发现有一个很久之前禁用的数据库维护作业，于是遂删除该作业，但是删除该作业时，遇到如下错误：

    脚本删除操作：

USE [msdb]
GO
EXEC msdb.dbo.sp_delete_job @job_id=N'876ab683-6d81-47c4-bba2-0dfa58156110',
@delete_unused_schedule=1
GO

消息 547，级别 16，状态 0，过程 sp_delete_job，第 178 行
The DELETE statement conflicted with the REFERENCE constraint "FK_subplan_job_id". The conflict occurred in database "msdb",
table "dbo.sysmaintplan_subplans", column 'job_id'.The statement has been terminated.

       图形界面操作:

 

案例分析：

从错误信息我们可以看出是删除某个系统表中记录时，由于外键约束关系，导致删除失败。最后导致存储过程msdb.dbo.sp_delete_job执行失败。我想彻底弄清楚删除失败的具体原因，于是可以从提示信息的系统表dbo.sysmaintplan_subplans开始，如下所示，

可以看到系统表dbo.sysmaintplan_subplans中的job_id字段引用了msdb.dbo.sysjobs中的job_id字段，那么可以肯定是在删除msdb.dbo.sysjobs表中对应记录时，没有先删除dbo.sysmaintplan_subplans中的记录。这样推测也跟报错信息吻合。

那么接下来我们研究一下msdb数据库的存储过程[dbo].[sp_delete_job] 如下所示：

USE [msdb]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[sp_delete_job]
  @job_id UNIQUEIDENTIFIER = NULL, -- If provided should NOT also provide job_name
  @job_name sysname = NULL, -- If provided should NOT also provide job_id
  @originating_server sysname = NULL, -- Reserved (used by SQLAgent)
  @delete_history BIT = 1, -- Reserved (used by SQLAgent)
  @delete_unused_schedule BIT = 1 -- For backward compatibility schedules are deleted by default if they are not
                                        -- being used by another job. With the introduction of reusable schedules in V9
                                        -- callers should set this to 0 so the schedule will be preserved for reuse.
AS
BEGIN
  DECLARE @current_msx_server sysname
  DECLARE @bMSX_job BIT
  DECLARE @retval INT
  DECLARE @local_machine_name sysname
  DECLARE @category_id INT
  DECLARE @job_owner_sid VARBINARY(85)

  SET NOCOUNT ON
  -- Remove any leading/trailing spaces from parameters
  SELECT @originating_server = UPPER(LTRIM(RTRIM(@originating_server)))
  -- Turn [nullable] empty string parameters into NULLs
  IF (@originating_server = N'') SELECT @originating_server = NULL
  -- Change server name to always reflect real servername or servernameinstancename
  IF (@originating_server IS NOT NULL AND @originating_server = '(LOCAL)')
    SELECT @originating_server = UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName')))
  IF ((@job_id IS NOT NULL) OR (@job_name IS NOT NULL))
  BEGIN
    EXECUTE @retval = sp_verify_job_identifiers '@job_name',
                                                '@job_id',
                                                 @job_name OUTPUT,
                                                 @job_id OUTPUT,
                                                 @owner_sid = @job_owner_sid OUTPUT
    IF (@retval <> 0)
      RETURN(1) -- Failure
  END
  -- We need either a job name or a server name, not both
  IF ((@job_name IS NULL) AND (@originating_server IS NULL)) OR
     ((@job_name IS NOT NULL) AND (@originating_server IS NOT NULL))
  BEGIN
    RAISERROR(14279, -1, -1)
    RETURN(1) -- Failure
  END
  -- Get category to see if it is a misc. replication agent. @category_id will be
  -- NULL if there is no @job_id.
  select @category_id = category_id from msdb.dbo.sysjobs where job_id = @job_id
  -- If job name was given, determine if the job is from an MSX
  IF (@job_id IS NOT NULL)
  BEGIN
    SELECT @bMSX_job = CASE UPPER(originating_server)
                         WHEN UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName'))) THEN 0
                         ELSE 1
                       END
    FROM msdb.dbo.sysjobs_view
    WHERE (job_id = @job_id)
  END
  -- If server name was given, warn user if different from current MSX
  IF (@originating_server IS NOT NULL)
  BEGIN
    EXECUTE @retval = master.dbo.xp_getnetname @local_machine_name OUTPUT
    IF (@retval <> 0)
      RETURN(1) -- Failure
    IF ((@originating_server = UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName')))) OR (@originating_server = UPPER(@local_machine_name)))
      SELECT @originating_server = UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName')))
    EXECUTE master.dbo.xp_instance_regread N'HKEY_LOCAL_MACHINE',
                                           N'SOFTWAREMicrosoftMSSQLServerSQLServerAgent',
                                           N'MSXServerName',
                                           @current_msx_server OUTPUT,
                                           N'no_output'
    SELECT @current_msx_server = UPPER(@current_msx_server)
    -- If server name was given but it's not the current MSX, print a warning
    SELECT @current_msx_server = LTRIM(RTRIM(@current_msx_server))
    IF ((@current_msx_server IS NOT NULL) AND (@current_msx_server <> N'') AND (@originating_server <> @current_msx_server))
      RAISERROR(14224, 0, 1, @current_msx_server)
  END
  -- Check authority (only SQLServerAgent can delete a non-local job)
  IF (((@originating_server IS NOT NULL) AND (@originating_server <> UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName'))))) OR (@bMSX_job = 1)) AND
     (PROGRAM_NAME() NOT LIKE N'SQLAgent%')
  BEGIN
    RAISERROR(14274, -1, -1)
    RETURN(1) -- Failure
  END

  -- Check permissions beyond what's checked by the sysjobs_view
  -- SQLAgentReader and SQLAgentOperator roles that can see all jobs
  -- cannot delete jobs they do not own
  IF (@job_id IS NOT NULL)
  BEGIN
   IF (@job_owner_sid <> SUSER_SID() -- does not own the job
       AND (ISNULL(IS_SRVROLEMEMBER(N'sysadmin'), 0) <> 1)) -- is not sysadmin
   BEGIN
     RAISERROR(14525, -1, -1);
     RETURN(1) -- Failure
    END
  END
  -- Do the delete (for a specific job)
  IF (@job_id IS NOT NULL)
  BEGIN
    -- Note: This temp table is referenced by msdb.dbo.sp_delete_job_references
    CREATE TABLE #temp_jobs_to_delete (job_id UNIQUEIDENTIFIER NOT NULL, job_is_cached INT NOT NULL)
    DECLARE @temp_schedules_to_delete TABLE (schedule_id INT NOT NULL)
    INSERT INTO #temp_jobs_to_delete
    SELECT job_id, (SELECT COUNT(*)
                    FROM msdb.dbo.sysjobservers
                    WHERE (job_id = @job_id)
                      AND (server_id = 0))
    FROM msdb.dbo.sysjobs_view
    WHERE (job_id = @job_id)
    -- Check if we have any work to do
    IF (NOT EXISTS (SELECT *
                    FROM #temp_jobs_to_delete))
    BEGIN
      DROP TABLE #temp_jobs_to_delete
      RETURN(0) -- Success
    END
    -- Post the delete to any target servers (need to do this BEFORE
    -- deleting the job itself, but AFTER clearing all all pending
    -- download instructions). Note that if the job is NOT a
    -- multi-server job then sp_post_msx_operation will catch this and
    -- will do nothing. Since it will do nothing that is why we need
    -- to NOT delete any pending delete requests, because that delete
    -- request might have been for the last target server and thus
    -- this job isn't a multi-server job anymore so posting the global
    -- delete would do nothing.
    DELETE FROM msdb.dbo.sysdownloadlist
    WHERE (object_id = @job_id)
      and (operation_code != 3) -- Delete
    EXECUTE msdb.dbo.sp_post_msx_operation 'DELETE', 'JOB', @job_id
    -- Must do this before deleting the job itself since sp_sqlagent_notify does a lookup on sysjobs_view
    -- Note: Don't notify agent in this call. It is done after the transaction is committed
    -- just in case this job is in the process of deleting itself
    EXECUTE msdb.dbo.sp_delete_job_references @notify_sqlagent = 0
    -- Delete all traces of the job
    BEGIN TRANSACTION
   --Get the schedules to delete before deleting records from sysjobschedules
    IF(@delete_unused_schedule = 1)
    BEGIN
        --Get the list of schedules to delete
        INSERT INTO @temp_schedules_to_delete
        SELECT DISTINCT schedule_id
        FROM msdb.dbo.sysschedules
        WHERE (schedule_id IN
                (SELECT schedule_id
                FROM msdb.dbo.sysjobschedules
                WHERE (job_id = @job_id)))
    END
    DELETE FROM msdb.dbo.sysjobschedules
    WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)

    DELETE FROM msdb.dbo.sysjobservers
    WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)
    DELETE FROM msdb.dbo.sysjobsteps
    WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)
    DELETE FROM msdb.dbo.sysjobs
    WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)

    --Delete the schedule(s) if requested to and it isn't being used by other jobs
    IF(@delete_unused_schedule = 1)
    BEGIN
      --Now OK to delete the schedule
      DELETE FROM msdb.dbo.sysschedules
      WHERE schedule_id IN
        (SELECT schedule_id
         FROM @temp_schedules_to_delete as sdel
         WHERE NOT EXISTS(SELECT *
                          FROM msdb.dbo.sysjobschedules AS js
                          WHERE (js.schedule_id = sdel.schedule_id)))
    END
    -- Delete the job history if requested
    IF (@delete_history = 1)
    BEGIN
      DELETE FROM msdb.dbo.sysjobhistory
      WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)
    END
    -- All done
    COMMIT TRANSACTION
    -- Now notify agent to delete the job.
    IF(EXISTS(SELECT * FROM #temp_jobs_to_delete WHERE job_is_cached > 0))
    BEGIN
      DECLARE @nt_user_name NVARCHAR(100)
      SELECT @nt_user_name = ISNULL(NT_CLIENT(), ISNULL(SUSER_SNAME(), FORMATMESSAGE(14205)))
      --Call the xp directly. sp_sqlagent_notify checks sysjobs_view and the record has already been deleted
      EXEC master.dbo.xp_sqlagent_notify N'J', @job_id, 0, 0, N'D', @nt_user_name, 1, @@trancount, NULL, NULL
    END
  END
  ELSE
  -- Do the delete (for all jobs originating from the specific server)
  IF (@originating_server IS NOT NULL)
  BEGIN
    EXECUTE msdb.dbo.sp_delete_all_msx_jobs @msx_server = @originating_server
    -- NOTE: In this case there is no need to propagate the delete via sp_post_msx_operation
    -- since this type of delete is only ever performed on a TSX.
  END
  IF (OBJECT_ID(N'tempdb.dbo.#temp_jobs_to_delete', 'U') IS NOT NULL)
    DROP TABLE #temp_jobs_to_delete
  RETURN(0) -- 0 means success
END

从上面SQL脚本中可以看到在删除msdb.dbo.sysjobsteps之前，该存储过程执行了msdb.dbo.sp_delete_job_references

USE [msdb]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER OFF
GO
ALTER PROCEDURE [dbo].[sp_delete_job_references]
  @notify_sqlagent BIT = 1
AS
BEGIN
  DECLARE @deleted_job_id UNIQUEIDENTIFIER
  DECLARE @task_id_as_char VARCHAR(10)
  DECLARE @job_is_cached INT
  DECLARE @alert_name sysname
  DECLARE @maintplan_plan_id UNIQUEIDENTIFIER
  DECLARE @maintplan_subplan_id UNIQUEIDENTIFIER

  -- Keep SQLServerAgent's cache in-sync and cleanup any 'webtask' cross-references to the deleted job(s)
  -- NOTE: The caller must have created a table called #temp_jobs_to_delete of the format
  -- (job_id UNIQUEIDENTIFIER NOT NULL, job_is_cached INT NOT NULL).

  DECLARE sqlagent_notify CURSOR LOCAL
  FOR
  SELECT job_id, job_is_cached
  FROM #temp_jobs_to_delete

  OPEN sqlagent_notify
  FETCH NEXT FROM sqlagent_notify INTO @deleted_job_id, @job_is_cached

  WHILE (@@fetch_status = 0)
  BEGIN
    -- NOTE: We only notify SQLServerAgent if we know the job has been cached
    IF(@job_is_cached = 1 AND @notify_sqlagent = 1)
      EXECUTE msdb.dbo.sp_sqlagent_notify @op_type = N'J',
                                          @job_id = @deleted_job_id,
                                          @action_type = N'D'

    IF (EXISTS (SELECT *
                FROM master.dbo.sysobjects
                WHERE (name = N'sp_cleanupwebtask')
                  AND (type = 'P')))
    BEGIN
      SELECT @task_id_as_char = CONVERT(VARCHAR(10), task_id)
      FROM msdb.dbo.systaskids
      WHERE (job_id = @deleted_job_id)
      IF (@task_id_as_char IS NOT NULL)
        EXECUTE ('master.dbo.sp_cleanupwebtask @taskid = ' + @task_id_as_char)
    END

    -- Maintenance plan cleanup for SQL 2005.
    -- If this job came from another server and it runs a subplan of a
    -- maintenance plan, then delete the subplan record. If that was
    -- the last subplan still referencing that plan, delete the plan.
    -- This removes a distributed maintenance plan from a target server
    -- once all of jobs from the master server that used that maintenance
    -- plan are deleted.
    SELECT @maintplan_plan_id = plans.plan_id, @maintplan_subplan_id = plans.subplan_id
    FROM sysmaintplan_subplans plans, sysjobs_view sjv
    WHERE plans.job_id = @deleted_job_id
      AND plans.job_id = sjv.job_id
      AND sjv.master_server = 1 -- This means the job came from the master

    IF (@maintplan_subplan_id is not NULL)
    BEGIN
      EXECUTE sp_maintplan_delete_subplan @subplan_id = @maintplan_subplan_id, @delete_jobs = 0
      IF (NOT EXISTS (SELECT *
                      FROM sysmaintplan_subplans
                      where plan_id = @maintplan_plan_id))
      BEGIN
        DECLARE @plan_name sysname

        SELECT @plan_name = name
          FROM sysmaintplan_plans
          WHERE id = @maintplan_plan_id

        EXECUTE sp_dts_deletepackage @name = @plan_name, @folderid = '08aa12d5-8f98-4dab-a4fc-980b150a5dc8' -- this is the guid for 'Maintenance Plans'
      END
    END

    FETCH NEXT FROM sqlagent_notify INTO @deleted_job_id, @job_is_cached
  END
  DEALLOCATE sqlagent_notify

  -- Remove systaskid references (must do this AFTER sp_cleanupwebtask stuff)
  DELETE FROM msdb.dbo.systaskids
  WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)

  -- Remove sysdbmaintplan_jobs references (legacy maintenance plans prior to SQL 2005)
  DELETE FROM msdb.dbo.sysdbmaintplan_jobs
  WHERE job_id IN (SELECT job_id FROM #temp_jobs_to_delete)

  -- Finally, clean up any dangling references in sysalerts to the deleted job(s)
  DECLARE sysalerts_cleanup CURSOR LOCAL
  FOR
  SELECT name
  FROM msdb.dbo.sysalerts
  WHERE (job_id IN (SELECT job_id FROM #temp_jobs_to_delete))

  OPEN sysalerts_cleanup
  FETCH NEXT FROM sysalerts_cleanup INTO @alert_name
  WHILE (@@fetch_status = 0)
  BEGIN
    EXECUTE msdb.dbo.sp_update_alert @name = @alert_name,
                                     @job_id = 0x00
    FETCH NEXT FROM sysalerts_cleanup INTO @alert_name
  END
  DEALLOCATE sysalerts_cleanup
END

而msdb.dbo.sp_delete_job_references这个存储过程又接着调用了存储过程sp_maintplan_delete_subplan，

USE [msdb]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER OFF
GO
ALTER PROCEDURE [dbo].[sp_maintplan_delete_subplan]
    @subplan_id UNIQUEIDENTIFIER,
    @delete_jobs BIT = 1
AS
BEGIN

    DECLARE @retval INT
    DECLARE @job UNIQUEIDENTIFIER
    DECLARE @jobMsx UNIQUEIDENTIFIER

    SET NOCOUNT ON
    SET @retval = 0

    -- Raise an error if the @subplan_id doesn't exist
    IF( NOT EXISTS(SELECT * FROM sysmaintplan_subplans WHERE subplan_id = @subplan_id))
    BEGIN
        DECLARE @subplan_id_as_char VARCHAR(36)
        SELECT @subplan_id_as_char = CONVERT(VARCHAR(36), @subplan_id)
        RAISERROR(14262, -1, -1, '@subplan_id', @subplan_id_as_char)
        RETURN(1)
    END


    BEGIN TRAN

    --Is there an Agent Job/Schedule associated with this subplan?
    SELECT @job = job_id, @jobMsx = msx_job_id
    FROM msdb.dbo.sysmaintplan_subplans
    WHERE subplan_id = @subplan_id

    EXEC @retval = msdb.dbo.sp_maintplan_delete_log @subplan_id = @subplan_id
    IF (@retval <> 0)
    BEGIN
        ROLLBACK TRAN
        RETURN @retval
    END

    -- Delete the subplans table entry first since it has a foreign
    -- key constraint on its job_id existing in sysjobs.
    DELETE msdb.dbo.sysmaintplan_subplans
    WHERE (subplan_id = @subplan_id)

    IF (@delete_jobs = 1)
    BEGIN
        --delete the local job associated with this subplan
        IF (@job IS NOT NULL)
        BEGIN
            EXEC @retval = msdb.dbo.sp_delete_job @job_id = @job, @delete_unused_schedule = 1
            IF (@retval <> 0)
            BEGIN
                ROLLBACK TRAN
                RETURN @retval
            END
        END

        --delete the multi-server job associated with this subplan.
        IF (@jobMsx IS NOT NULL)
        BEGIN
            EXEC @retval = msdb.dbo.sp_delete_job @job_id = @jobMsx, @delete_unused_schedule = 1
            IF (@retval <> 0)
            BEGIN
                ROLLBACK TRAN
                RETURN @retval
            END
        END
    END

    COMMIT TRAN
    RETURN (0)
END

也就是说最终在此存储过程sp_maintplan_delete_subplan中删除msdb.dbo.sysmaintplan_subplans 表中的记录。 过程梳理清楚了，那么逆向推导看看具体原因

如下所示，删除msdb.dbo.sysmaintplan_subplans中对应记录语句如下

此时要看参数@subplan_id的取值，它从msdb.dbo.sp_delete_job_references中传入，如下所示

ALTER PROCEDURE [dbo].[sp_maintplan_delete_subplan]

    @subplan_id UNIQUEIDENTIFIER,

    @delete_jobs BIT = 1

AS

…………………………………………………………………

在[dbo].[sp_delete_job_references]中，它的值来自于 @maintplan_subplan_id变量，最终来自于sysmaintplan_subplans系统表

SELECT @maintplan_plan_id = plans.plan_id,
       @maintplan_subplan_id = plans.subplan_id
    FROM sysmaintplan_subplans plans, sysjobs_view sjv
    WHERE plans.job_id = @deleted_job_id
      AND plans.job_id = sjv.job_id
      AND sjv.master_server = 1 -- This means the job came from the master

我通过DAC登录数据库（sysmaintplan_subplans是内部对象，此对象在DAC下才可以访问），查询如下所示，你会发现无记录，也就是说@maintplan_subplan_id为NULL值，导致后面执行删除msdb.dbo.sysmaintplan_subplans表中记录时，没有真正的删除记录。

 

最后发现导致查询无记录的原因在于查询条件sjv.master_server = 1

sysjob_view视图代码如下所示：

CREATE VIEW sysjobs_view
AS
SELECT jobs.job_id,
       svr.originating_server,
       jobs.name,
       jobs.enabled,
       jobs.description,
       jobs.start_step_id,
       jobs.category_id,
       jobs.owner_sid,
       jobs.notify_level_eventlog,
       jobs.notify_level_email,
       jobs.notify_level_netsend,
       jobs.notify_level_page,
       jobs.notify_email_operator_id,
       jobs.notify_netsend_operator_id,
       jobs.notify_page_operator_id,
       jobs.delete_level,
       jobs.date_created,
       jobs.date_modified,
       jobs.version_number,
       jobs.originating_server_id,
       svr.master_server
FROM msdb.dbo.sysjobs as jobs
  JOIN msdb.dbo.sysoriginatingservers_view as svr
    ON jobs.originating_server_id = svr.originating_server_id
  --LEFT JOIN msdb.dbo.sysjobservers js ON jobs.job_id = js.job_id
WHERE (owner_sid = SUSER_SID())
   OR (ISNULL(IS_SRVROLEMEMBER(N'sysadmin'), 0) = 1)
   OR (ISNULL(IS_MEMBER(N'SQLAgentReaderRole'), 0) = 1)
   OR ( (ISNULL(IS_MEMBER(N'TargetServersRole'), 0) = 1) AND
        (EXISTS(SELECT * FROM msdb.dbo.sysjobservers js
         WHERE js.server_id <> 0 AND js.job_id = jobs.job_id))) -- filter out local jobs

继续往下扒，视图dbo.sysoriginatingservers_view代码如下所示，

CREATE VIEW dbo.sysoriginatingservers_view(originating_server_id, originating_server, master_server)
AS
   SELECT
      0 AS originating_server_id,
      UPPER(CONVERT(sysname, SERVERPROPERTY('ServerName'))) AS originating_server,
      0 AS master_server
   UNION
   SELECT
      originating_server_id,
      originating_server,
      master_server
   FROM
      dbo.sysoriginatingservers

原来master_server的值是默认的。因为表dbo.sysoriginatingservers无记录。至此，可以看出，这应该是SQL Server 2005的一个BUG来的。

解决方案：

手工删除系统表msdb.dbo.sysmaintplan_subplans中的记录，然后删除该作业。问题搞定。

USE [msdb]

GO

DELETE FROM msdb.dbo.sysmaintplan_subplans WHERE SUBPLAN_ID='B9A639EB-955D-4AE6-B69E-860145C133E7';

USE [msdb]

GO

EXEC msdb.dbo.sp_delete_job @job_id=N'ce8cb4ad-c91f-45bc-9e21-b50947063fba', @delete_unused_schedule=1

GO