Altering SQL Agent jobs during job runtime can give you some options as to how you can force other jobs
to react based on events. There are a listing of system procedures in the MSDB database available for
you to use so you can literally alter your entire timelines and schedules based on a failure, success or
even OS or network related issues. Here is a basic example of disabling and enabling a job
based on a monitoring task.

In this example there is a requirement to monitor a table that is being used to monitor finish good allocation
to a manufacturing facility to prevent volume from going over capacity.

Job 1 performs a monitoring task every 30 minutes. Basically querying the table that holds the count of the volume
the facility has received that day (starting at midnight). At midnight the volume is replenished by means of the value
specified in the same table. There is a need to monitor the capacity and once under 2000 units are remaining,
you are required to send notifications out to management. Notifications should go out once.
The key is the one notification. This is one option of getting around that using the system procedures to alter job properties.

Step 1) create the table to monitor

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SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[VOL_MONITOR](
    [VolumeID] [int] IDENTITY(1,1) NOT NULL,
    [Facility] [varchar](50) NOT NULL,
    [Volume] [int] NOT NULL,
    [Vol_Status] [int] NOT NULL,
 CONSTRAINT [PK_VOL_MONITOR] PRIMARY KEY CLUSTERED 
(
    [VolumeID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, 
            IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, 
            ALLOW_PAGE_LOCKS  = ON, FILLFACTOR = 90) ON [PRIMARY]
) ON [PRIMARY]
 
GO
SET ANSI_PADDING OFF
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[VOL_MONITOR](
	[VolumeID] [int] IDENTITY(1,1) NOT NULL,
	[Facility] [varchar](50) NOT NULL,
	[Volume] [int] NOT NULL,
	[Vol_Status] [int] NOT NULL,
 CONSTRAINT [PK_VOL_MONITOR] PRIMARY KEY CLUSTERED 
(
	[VolumeID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, 
			IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, 
			ALLOW_PAGE_LOCKS  = ON, FILLFACTOR = 90) ON [PRIMARY]
) ON [PRIMARY]

GO
SET ANSI_PADDING OFF

Insert the data in order to test out monitor

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INSERT INTO DBO.[VOL_MONITOR]
VALUES ('AL Plant 1',20000,15000)
INSERT INTO DBO.[VOL_MONITOR]
VALUES ('AL Plant 1',20000,15000)

Step 2) create the job to monitor the volume count.

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DECLARE @jobId BINARY(16)
EXEC @ReturnCode =  msdb.dbo.sp_add_job @job_name=N'Capacity Restriction Monitor Plant 01', 
        @enabled=1, 
        @notify_level_eventlog=0, 
        @notify_level_email=0, 
        @notify_level_netsend=0, 
        @notify_level_page=0, 
        @delete_level=0, 
        @description=N'Monitors the levels of units allowe to be manufactured in plant 01.', 
        @category_name=N'[Uncategorized (Local)]', 
        @owner_login_name=N'{user}', @job_id = @jobId OUTPUT
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
/****** Object:  Step [caller]    Script Date: 03/26/2009 08:31:35 ******/
EXEC @ReturnCode = msdb.dbo.sp_add_jobstep @job_id=@jobId, @step_name=N'caller', 
        @step_id=1, 
        @cmdexec_success_code=0, 
        @on_success_action=1, 
        @on_success_step_id=0, 
        @on_fail_action=2, 
        @on_fail_step_id=0, 
        @retry_attempts=0, 
        @retry_interval=0, 
        @os_run_priority=0, @subsystem=N'TSQL', 
        @command=N'if (select vol_status from VOL_MONITOR) <= 2000
          Begin
            EXEC msdb.dbo.sp_send_dbmail @recipients=''manager_group@companym.com'',
                @subject = ''Plant 01 volume reaching maximum capacity'',
                @body = ''Plant 01 volume reaching maximum capacity'',
                @body_format = ''HTML'',
                @profile_name = ''DBA01''
          End', 
        @database_name=N'DBA05', 
        @flags=0
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_update_job @job_id = @jobId, @start_step_id = 1
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_add_jobschedule @job_id=@jobId, @name=N'30 minutes', 
        @enabled=1, 
        @freq_type=4, 
        @freq_interval=1, 
        @freq_subday_type=4, 
        @freq_subday_interval=30, 
        @freq_relative_interval=0, 
        @freq_recurrence_factor=0, 
        @active_start_date=20090324, 
        @active_end_date=99991231, 
        @active_start_time=0, 
        @active_end_time=235959
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_add_jobserver @job_id = @jobId, @server_name = N'(local)'
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
COMMIT TRANSACTION
GOTO EndSave
QuitWithRollback:
    IF (@@TRANCOUNT > 0) ROLLBACK TRANSACTION
EndSave:
DECLARE @jobId BINARY(16)
EXEC @ReturnCode =  msdb.dbo.sp_add_job @job_name=N'Capacity Restriction Monitor Plant 01', 
		@enabled=1, 
		@notify_level_eventlog=0, 
		@notify_level_email=0, 
		@notify_level_netsend=0, 
		@notify_level_page=0, 
		@delete_level=0, 
		@description=N'Monitors the levels of units allowe to be manufactured in plant 01.', 
		@category_name=N'[Uncategorized (Local)]', 
		@owner_login_name=N'{user}', @job_id = @jobId OUTPUT
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
/****** Object:  Step [caller]    Script Date: 03/26/2009 08:31:35 ******/
EXEC @ReturnCode = msdb.dbo.sp_add_jobstep @job_id=@jobId, @step_name=N'caller', 
		@step_id=1, 
		@cmdexec_success_code=0, 
		@on_success_action=1, 
		@on_success_step_id=0, 
		@on_fail_action=2, 
		@on_fail_step_id=0, 
		@retry_attempts=0, 
		@retry_interval=0, 
		@os_run_priority=0, @subsystem=N'TSQL', 
		@command=N'if (select vol_status from VOL_MONITOR) <= 2000
		  Begin
			EXEC msdb.dbo.sp_send_dbmail @recipients=''manager_group@companym.com'',
				@subject = ''Plant 01 volume reaching maximum capacity'',
				@body = ''Plant 01 volume reaching maximum capacity'',
				@body_format = ''HTML'',
				@profile_name = ''DBA01''
		  End', 
		@database_name=N'DBA05', 
		@flags=0
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_update_job @job_id = @jobId, @start_step_id = 1
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_add_jobschedule @job_id=@jobId, @name=N'30 minutes', 
		@enabled=1, 
		@freq_type=4, 
		@freq_interval=1, 
		@freq_subday_type=4, 
		@freq_subday_interval=30, 
		@freq_relative_interval=0, 
		@freq_recurrence_factor=0, 
		@active_start_date=20090324, 
		@active_end_date=99991231, 
		@active_start_time=0, 
		@active_end_time=235959
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
EXEC @ReturnCode = msdb.dbo.sp_add_jobserver @job_id = @jobId, @server_name = N'(local)'
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
COMMIT TRANSACTION
GOTO EndSave
QuitWithRollback:
    IF (@@TRANCOUNT > 0) ROLLBACK TRANSACTION
EndSave:

So far we have successfully created a table to hold our capacity values that we negate based on units
sent to eh facility and we have a job to monitor the capacity. Problem is the job will send out an
email to management every 30 minutes which is not something managers like much. In order to keep the
DBA from manually going in after the notification is sent we need to disable the job. We can
use sp_udpate_job to get that task done.

First query the sysjob table in MSDB to grab the job_id. You can also use the name of the job but I
think that is prone to typos and copying the job_id directly out of sysjob is a bit more stable.

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select job_id,[name] from msdb.dbo.sysjobs
select job_id,[name] from msdb.dbo.sysjobs

This shows “8386ED61-E2A8-4DE5-B54C-4A7DFD3CDDEC” for the Capacity Restriction Monitor Plant 01 job_id

Syntax for sp_update_job is as follows. One key note is you can use job_name or job_id to update the job with
this system procedure BUT you cannot specify both. Other questions I hear are does the SP update other properties
when you do not specify them. The answer is no, the SP will only update what parameter you specify.

syntax

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sp_update_job [ @job_id =] job_id | [@job_name =] 'job_name'
     [, [@new_name =] 'new_name' ] 
     [, [@enabled =] enabled ]
     [, [@description =] 'description' ] 
     [, [@start_step_id =] step_id ]
     [, [@category_name =] 'category' ] 
     [, [@owner_login_name =] 'login' ]
     [, [@notify_level_eventlog =] eventlog_level ]
     [, [@notify_level_email =] email_level ]
     [, [@notify_level_netsend =] netsend_level ]
     [, [@notify_level_page =] page_level ]
     [, [@notify_email_operator_name =] 'email_name' ]
          [, [@notify_netsend_operator_name =] 'netsend_operator' ]
          [, [@notify_page_operator_name =] 'page_operator' ]
     [, [@delete_level =] delete_level ] 
     [, [@automatic_post =] automatic_post ]
sp_update_job [ @job_id =] job_id | [@job_name =] 'job_name'
     [, [@new_name =] 'new_name' ] 
     [, [@enabled =] enabled ]
     [, [@description =] 'description' ] 
     [, [@start_step_id =] step_id ]
     [, [@category_name =] 'category' ] 
     [, [@owner_login_name =] 'login' ]
     [, [@notify_level_eventlog =] eventlog_level ]
     [, [@notify_level_email =] email_level ]
     [, [@notify_level_netsend =] netsend_level ]
     [, [@notify_level_page =] page_level ]
     [, [@notify_email_operator_name =] 'email_name' ]
          [, [@notify_netsend_operator_name =] 'netsend_operator' ]
          [, [@notify_page_operator_name =] 'page_operator' ]
     [, [@delete_level =] delete_level ] 
     [, [@automatic_post =] automatic_post ]

So to form this call and disable the job we need to add to the job this statement.

After the db mail send put issue a Go and then add

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Exec msdb.dbo.sp_update_job @job_id = '8386ED61-E2A8-4DE5-B54C-4A7DFD3CDDEC' , @enabled = 0
Exec msdb.dbo.sp_update_job @job_id = '8386ED61-E2A8-4DE5-B54C-4A7DFD3CDDEC' , @enabled = 0

Now when the job runs it will send the notifications out and disable the job so no further
notifications will be sent.

Every night at midnight we stated the volume should be replenished to the maximum allowed units. This is
simply another job to reset the Vol_Status in our table to the value in Volume. The added requirement we need to
add to that job is re-enabling out monitor. If we don’t then the call to change the enable value in sysjob will remain
0 and the we break out monitoring process. So create another job scheduled for midnight with the statement of

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Update mem_vol set vol_status = volume
Go
Exec msdb..sp_update_job @job_id = '8386ED61-E2A8-4DE5-B54C-4A7DFD3CDDEC' , @enabled = 1
Go
Update mem_vol set vol_status = volume
Go
Exec msdb..sp_update_job @job_id = '8386ED61-E2A8-4DE5-B54C-4A7DFD3CDDEC' , @enabled = 1
Go

Now the process has gone through a complete cycle and the monitor and volume count starts clean.