About the issue that the file covers.

The program realized the function of backup database, in the Backup folder that acquiesce deposits the file after backup to fall in Sql, the file that backs up every time so maintains presence with respect to acquiesce over there.
I think implementation backs up every time now enclothe the document with file same name, how does everybody code excuse me implementation.
Thank, did not divide, to living everybody! Next having is examined when backing up every time the file exists, existence deletes cough up! But file of the Pubs after backup cannot be deleted at all, the program hints it is being called by other line Cheng.