Brad’s Sure Guide to SQL Server Maintenance Plans- P28 ppt

As discussed in the introduction, if you find yourself wanting to add multiple SQL Server Agent jobs to the plans you're creating using the Wizard, you're probably better off avoiding th

For example, you may have a custom job that:

• checks disk space and sends you a warning if it's getting near full

• kicks off a SQL Trace script to capture trace data on a scheduled basis

• checks a particular value, or values, in a DMV that you are interested in monitoring, and sends you an alert if the value(s) exceeds a predefined threshold

• starts a job that copies local MDF and LDF backups from off the local SQL Server instance

to another server location (preferably offsite)

As discussed in the introduction, if you find yourself wanting to add multiple SQL Server Agent jobs to the plans you're creating using the Wizard, you're probably better off avoiding the Wizard in the first place, and using T-SQL or PowerShell scripting

When the Execute SQL Server Agent Job task runs, T-SQL similar to the following

is executed

EXEC msdb.dbo.sp_start_job @job_id=N'cb73ea96-9a96-49fe-ada9-a70a941f9fb9'

Notice that this is the execution of a system-stored procedure, which is instructed to run a job with a specified internal number The number is not very useful to us, but if you want to look it up, in order to find out exactly what job was run (assuming you don't know), you could run the following SELECT statement:

SELECT * FROM msdb.dbo.sysjobs_view

This query will display all job IDs, along with their job names, so you can easily identify which job ID matches which job name

When an Execute SQL Server Agent Job task runs, it produces a text report similar to the following:

Microsoft(R) Server Maintenance Utility (Unicode) Version

10.0.2531

Report was generated on "HAWAII."

Maintenance Plan: MaintenancePlan

Success

Command:EXEC msdb.dbo.sp_start_job @job_id=N''cb73ea96-9a96-49fe-ada9-a70a941f9fb9''

GO

Given that the Execute SQL Server Agent Job task can only run a single job, this report is not very long You may want to note that the name of the job is included in the report, which can make it easier to troubleshoot potential problems with this task, should one arise

When and How Often to Run the

Custom Job

When and how often you run this job will depend on what the SQL Server Agent job does

If you are running a very lightweight job, such as checking disk space, you can run it almost whenever you want, and as often as you want On the other hand, if the SQL Server Agent job uses a lot of server resources to run, and/or takes a long time to run, then you will have

to schedule the job so that it doesn't interfere with users accessing the database, or with the running of other jobs Ideally, you will schedule it during available maintenance windows

Creating SQL Server Agent Jobs

If you decide to use the Execute SQL Server Agent Job task, you'll first need to create and configure the custom SQL Server Agent job that you want to run as part of your plan How

to create a SQL Server Agent job is beyond the scope of this book, but is explained in Books Online

You'd create the job just like you would any other SQL Server Agent job, except that you won't schedule it, as you will use the Maintenance Plan Wizard to do the scheduling of the job for you In addition, you will want to ensure that the SQL Server Agent job has been properly created and works as expected before you add it to a Maintenance Plan

Configuring the Execute SQL Server Agent Job Task

The Define Execute SQL Server Agent Job Task screen is very straightforward Your only

options are to choose the single job that you want to execute as part of the plan, and schedule when the job is to run

Selecting the Job

Figure 10.1 shows some the available SQL Server Agent jobs on my server Every SQL Server Agent job on the server will be displayed, and you may have to scroll down to see them all If you don't see any SQL Server Agent jobs listed in the Wizard, then you haven't created any, and should refer to the previous section!

Notice, in Figure 10.1, that there are checkboxes next to each job, giving the impression that you should be able to select multiple jobs from this screen and run them as part of your plan This is not the case If you select one checkbox, then another, the first checkbox you selected

is deselected and only the new one remains selected If Microsoft was following its own user interface design guidelines, there would be radio buttons here instead of checkboxes For this example, I've selected the Send Alert If Disk Space Exceeds 80% of Capacity job, as

the SQL Server Agent job I want included as part of my Maintenance Plan

Figure 10.1: You can only select one SQL Server Agent job to execute as part of a

Maintenance Plan.

Creating the Job Schedule

The next, and last step, as always, is to schedule when the task should run, using the Schedule

option Scheduling this task is like scheduling all the other tasks using the Maintenance Plan Wizard Ideally, the job should run during a maintenance window, or at least during a slower time of the day, and it should not overlap other plan tasks Your scheduling, of course, will have to take into account the resource impact of the SQL Server Agent job If the job

is lightweight, such as checking disk space, then you have great flexibility when running it But if the job is heavyweight, and uses a lot of SQL Server resources, then you will have to be much more careful about scheduling when, and how often, it runs

In theory, the Execute SQL Server Agent Job task is designed to add a little bit of flexibility

to Maintenance Plans created using the Maintenance Plan Wizard As long as you keep any Execute SQL Server Agent Job task simple and lightweight, you shouldn't run into any problems On the other hand, it is important not to misuse this feature, and try to make it perform tasks it is not really designed to do If you need database maintenance functionality that does not exist inside the Wizard, then take my advice (which by now may seem to be

a little repetitive), and consider performing your database maintenance using T-SQL or PowerShell scripts instead

In the next chapter, we learn about the History Cleanup task, which performs an important function many DBAs forget they need to carry out