Re: [sqlite] WAL mode and backup API
On 30.11.2010 11:50, Dan Kennedy wrote: > >> BTW: >> Is there any chance that in the future the wal mode >> will avoid that the backup API will restart on DB >> changes during the backup loop ? >> Currently, even in wal mode, it does restart when changes >> are detected while the backup is ongoing. > > What happens if you open a read transaction on the source database > before starting the backup? i.e. > > sqlite3_exec(pSource, "BEGIN; SELECT * FROM sqlite_master", 0, 0, 0); > > ... do backup ... > > sqlite3_exec(pSource, "COMMIT", 0, 0, 0); > > Does that help things any? wow... what a trick! Using your hint I'm not able to reproduce any restarts! I can imagine what your hint does in wal mode, but without your input I would never came to that idea... :-) Thanks Dan! This makes the wal mode and backup API even more sexy. Marcus > ___ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] WAL mode and backup API
> BTW: > Is there any chance that in the future the wal mode > will avoid that the backup API will restart on DB > changes during the backup loop ? > Currently, even in wal mode, it does restart when changes > are detected while the backup is ongoing. What happens if you open a read transaction on the source database before starting the backup? i.e. sqlite3_exec(pSource, "BEGIN; SELECT * FROM sqlite_master", 0, 0, 0); ... do backup ... sqlite3_exec(pSource, "COMMIT", 0, 0, 0); Does that help things any? ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] WAL mode and backup API
On 30.11.2010 11:32, Dan Kennedy wrote: > On 11/30/2010 05:03 PM, Marco Bambini wrote: >> Hello, >> >> if a running sqlite database is in WAL mode and a backup is performed on >> that db using the sqlite3_backup API, does that process is considered like a >> reader and can proceed concurrently with other readers and with the other >> writer? >> > > Yes. The connection to the backup source acts like any other reader. BTW: Is there any chance that in the future the wal mode will avoid that the backup API will restart on DB changes during the backup loop ? Currently, even in wal mode, it does restart when changes are detected while the backup is ongoing. Marcus > ___ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] WAL mode and backup API
On 11/30/2010 05:03 PM, Marco Bambini wrote: > Hello, > > if a running sqlite database is in WAL mode and a backup is performed on that > db using the sqlite3_backup API, does that process is considered like a > reader and can proceed concurrently with other readers and with the other > writer? > Yes. The connection to the backup source acts like any other reader. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
