SQL Server Agent: job

There is one record for each job in msdb.dbo.sysjobs system table.

A job consists of one or more job steps. These are tracked in msdb.dbo.sysjobsteps.

The current state of each job per session is stored in msdb.dbo.sysjobactivity.

msdb.dbo.sysjobhistory records the execution of job steps, usually after a step finishes. (There are exceptions to this rule, however).

msdb.dbo.sysjobschedules links jobs and schedules. A job can be linked to multiple schedules, and a schedules can be linked to multiple jobs.

msdb.dbo.sysschedules

msdb.dbo.sysjobsteps

A job might be manipulated (for example inactivated) with msdb.dbo.sp_update_job.

A job can be started manually with msdb.dbo.sp_start_job

Jobs are executed by SQL Server Agent

sa Simple example for creating and scheduling SQL Server Agent jobs