SQL Server Agent Overview

SQL Server Agent is a Windows service that execute scheduled administrative tasks (Jobs) and notify operators when a specific SQL Server event occurs (Alerts).

Jobs:

• SQL Server Agent uses SQL Server to store job information.
• Jobs contain one or more job steps; job steps can define which specific job step should be executed when the current step succeeds / fails.
• Job steps can do different things, like
         - launch a console application
         - backing up a database using T-SQL.
         - run PowerShell script.
         - initiate data transfer task using SQL Server Integration Services.
         - running an MDX query on Analysis server.
• Results of job execution are stored in a history table for later analysis.
• Jobs can be defined to start on schedule or started ad-hoc using SSMS UI / T-SQL API / SMO managed object model / PowerShell.
• Jobs can also be started when a specific SQL Server event occurs. Example: Start a backup job whenever a new database was created / attached.

Alerts:

• Alert definitions are stored in MSDB database.
• Alert can be defined on a specific SQL Server error / information event.
• Alert can be triggered when a specific SQL Server performance counter exceeds a threshold value.

Notifications:

• SQL Agent can notify an operator when a job succeeds / fails.
• When an Alert condition is triggered, operator can be notified by sending emails using Database Mail.

Jobs, Alerts, operators can be defined using SSMS UI / T-SQL API / SMO managed object model / PowerShell.

More details in MSDN: http://msdn.microsoft.com/en-us/library/ms189237.aspx
Team Blog: http://blogs.msdn.com/b/sqlagent/

Forums:
Manageability: http://social.msdn.microsoft.com/Forums/en-US/sqlkjmanageability/threads
SQL Tools: http://social.msdn.microsoft.com/Forums/en-US/sqltools/threads
SMO: http://social.msdn.microsoft.com/Forums/en-US/sqlsmoanddmo/threads
Multi Server Management: http://social.msdn.microsoft.com/Forums/en-US/sqlkjappmsmgmt/threads

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