Murasoli,
Crontab is for UNIX. For Windows, you have to use windows scheduler. The third post on
this page describes the details. In the scheduler entry, you would run:
>java ProgramToDeleteFromDatabase
I assume you have a where clause in the delete query? You just write up a small program (with a main method) that uses JDBC to run the query. The code should look just like your JDBC code in the regular application.