Erasing Log File Data Before Restoring

You may want to give users the option to keep existing log file data already on the server and restore over it. After you restore the files and the service starts up, the database will commit the transactions in the restored log files. If contiguous log files exist on the server beyond the highest restored log file, those transactions will also be committed. If there is any gap in the numeric log file name sequence, however, no further transactions will be committed beyond the gap.

You should also provide the option to delete the existing log files on the disk because certain situations will require this (such as restoring an information store to a different server or purposely restoring to a previous date without desire for recommitting all the logs that are still on the disk). This can, of course, also be done manually by the user before running your program.