TAILIEUCHUNG - Brad’s Sure Guide to SQL Server Maintenance Plans- P19

Brad’s Sure Guide to SQL Server Maintenance Plans- P19: SQL Server has a reputation as being a simple database application to install, configure, and maintain. This is a little misleading. SQL Server is a powerful relational database that can handle the needs of the largest organizations and, as such, its proper maintenance almost certainly requires the attention of an experienced DBA. | Chapter 4 Task Scheduling If you want a task to run more than once a day then you must select the Occurs every option as shown in Figure . Daily frequency C Occurs once at 12 00 00 AM Occurs every 1 hour s t Starting at 12 00 00 AM p - Ending at 11 59 59 PM C Figure Events can be scheduled to occur multiple times a day. By default when you choose this option a job is to be executed every 1 hour. You can change the frequency the job runs along with the time scale hours minutes and seconds . For example you could schedule a job to run every 12 hours every 12 minutes or every 12 seconds. If this is not quite enough flexibility you have the option to control the time period within a day that jobs can run. The default value is a Starting at value of 12 00 00 . and an Ending at value of 11 59 59 . which is one second less than a full 24-hour day. This means that your job can run any time during a 24-hour day. If you want to prevent jobs from running during certain parts of the day simply change the Starting at and Ending at times. For example you might decide to restrict certain tasks to nighttime execution so as not to interfere with user activity. Job Duration The final choice you can make is to specify when your job schedule is to begin and optionally to end using the Duration option. The default shown in Figure is to start the job schedule on today s date with no end date. Duration Start date 7 7 2009 QH End date 7 7 2009 C No end date Figure You can determine when a job starts and ends. Alternatively you can specify the job schedule to begin at some future date or to end the job schedule at some future date. In the context of the Maintenance Plan Wizard you would rarely want to change either of these defaults as your goal is to start your jobs right away and have them run forever or until you decide to change or delete the job . The one exception I can think of is that you might want to delay a job from starting right now until a later date

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