No job history . can u pls tell us where the history is and how it deleted . and who delete it . In my jobs history all the job history is empty. wanted to know why is it so . Have checked is their any job which delete the history from job. Kindly history
Do you keep track of your databases size? In that case, you'll know rougly when it happened. loghistory is stored in a table in the MSDB database (sysjobhistory). Depending on auditing settings you can see who executed the "truncate table sysjobhistory", but I assume that's theoretical. Note: you can also delete log history with some stored procedures provided by SQL. Check also "SQL Server Agent" -> Properties -> History to see your history settings.
Job history is held in the sysjobhistory table in MSDB. Check the SQL Agent settings for how much job history it keeps - there are settings that may result in not seeing job history for some jobs, but plenty for others. It's not good - the settings are for maximum number of lines of history, and maximum number of lines of history per job. Sounds reasonable; however, if you have a job that runs every five minutes, and another that runs every month, you'll very rarely see any history for the latter.