Richard I read that the db on the standby machine is being updated at a record by record level, i.e. not copied in its entirety. In this scenario I can't see the two db files being guaranteed binary compatible. Copying the journal across in this scenario would imo be a mistake. Paul www.sandersonforensics.com skype: r3scue193 twitter: @sandersonforens Tel +44 (0)1326 572786 http://sandersonforensics.com/forum/content.php?195-SQLite-Forensic-Toolkit -Forensic Toolkit for SQLite email from a work address for a fully functional demo licence
On 13 February 2015 at 02:47, Richard Hipp <d...@sqlite.org> wrote: > On 2/12/15, Mayank Kumar (mayankum) <mayan...@cisco.com> wrote: >> Hi All >> >> We have two systems which are running in active/standby configuration. The >> active machine, is actively writing sqlite transactions to a file abcd.db. >> The standby is syncing the abcd.db file from the active machine on a >> communication channel and writing the delta records to the abcd.db on the >> standby machine. >> >> Now my question is , lets say the active machine crashes in the middle of >> the transaction and we have a hot journal created on the active machine. >> Does it make sense to copy the hot journal to the standby machine, so that >> the sqlite application on the standby will notice this hot journal and use >> it to recover any lost transactions > > Not only does it make sense - it is mandatory if you want to preserve > the integrity of the database file. > > While a transaction is underway, the journal (either the *-journal > file or the *-wal file) is part of the state of the database. If you > fail to copy it over to another machine and then try to open that > database on the other machine, the database will be incomplete and > potentially corrupt. > > The journal files have a well-defined and documented format. They are > independent of the byte-order and word-size of the machine they were > created on. > -- > D. Richard Hipp > d...@sqlite.org > _______________________________________________ > 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
