SQLite Forum

Hot backup database in WAL mode by coping
> That is a clear statement about writes. Reading the database works during holding that lock, and I don't see a reason why it should affect the Backup Process 2 is doing during that time.

Yes, and only the main database file needs to be backed up.  It will be consistent with the last checkpoint before the lock was taken.  The copy must be performed by a separate process (not thread).