Anonymous Coward DurumDara wrote: > [...] > So I want to use one database file - but I want to protect it. > How to do it with SQLite ? > I see that solutions: > - 1. I use transactions. > - 2. I create full copy of database after every bigger transation. > - 3. Shadow file ??? > - 4. Mirror database (this is problematic to synch.). > > The transactions are very good things, but does not protect the database > from injuring.
Actually, SQLite transactions do protect you from "bad things happening". If a transaction suceeds, it also does an fsync() call so that the data gets written to disk and does not remain in the database's or operating system's write cache. And of course, the main feature is that if you group your SQL statements right, then the database is always in a consistent state, even after a crash. > The copy operation is better, but very decrease the processing speed, > because the result db grow fast, and copy of 1/2,2/3 GBs is slow, and > not too good. and doesn't help the real problem at all. If your application or computer crashes during a copy, from where do you recover from? > Have SQLite any solution to this problem ? Transactions :-) And don't set PRAGMA synchronous = OFF; to increase the speed of your application, because then your database *will* be corrupted during a crash. (*) -- Gerhard (*) Full details at http://www.sqlite.org/pragma.html for PRAGMA synchronous. -- http://mail.python.org/mailman/listinfo/python-list
