Re: [Tracker] Rescue tracker db backup

[Philip Van Hoof <philip codeminded be>]

Hi Janis,

To be honest what could be developed would be a program that connects
with meta.db directly and that tries to make SQL queries on the
different tables and/or dumps the tables' data as text in a comma
separated value file or something.

And then another program that imports the data that could be recovered
as a new meta.db. With no guarantees that the newly created meta.db is
sufficient for normal operation for tracker-store. But with the current
data corruption in meta.db you don't have normal operation anyway. so
yeah.

I'm quite sure you're not the only one with this problem on hardware
like the N9. So development of such data recovery tools would probably
help Nokia's service centers and yourself more than whatever current
Nokia's service centers can help you now. Based on what I know ;)


Kind regards,

Philip


On Thu, 2012-12-13 at 21:37 +0100, Philip Van Hoof wrote:
> On Sun, 2012-12-02 at 03:41 +0200, JÄnis RukÅÄns wrote:
> > Hi,
> >
> > Every four months or so, my N9 decides to wipe out the tracker
> > database. I have no idea why this happens,
>
> Eh, as having been a N9 developer myself I can tell you with a straight
> face that this is absolutely not normal and that you should return your
> phone to a nearby Nokia service center.
>
> >  but previously I've been
> > able to get my contacts back by restoring from backup (made with
> > tracker-control -b), but not now. The kind folk on #tracker suggested
> > that reason why the restore isn't working might be Aegis going bananas
> > (there are warnings in the tracker-store.log about not being able to
> > move files to .cache/tracker/tmp/).
>
> Correct, Aegis makes it impossible for the normal user to tamper with
> Tracker's database directly. You'd need to root your device and chmod
> the directory in ~/.cache to gain access to the files.
>
> Note that you should completely shut down Tracker's process and that
> this isn't easy as your N9's other softwares will periodically
> reactivate it based on their needs. So those process must be shut down
> too to avoid this, while you are working with the files.
>
> I generally don't recommend this as doing it wrong can mean loss of
> data.
>
> > After some digging it turned out that restore fails because the backup
> > fails integrity checks (I guess that was also the reason of the wipe
> > out). Anyway, I can load the backup in sqlite3 CLI and dump it to SQL.
>
>
> Integrity check failure means that your N9 had a serious HW failure. For
> that you should return your device to a Nokia service center.
>
> Recovering your data will be very difficult.
>
> The problem is that making a backup of a sqlite database, using
> sqlite_backup API (which is what Tracker uses) can copy the corruption
> to the backup file. So once corrupted, making a backup and restoring
> that backup doesn't necessarily solve the problem.
>
> > My question is whether it is possible to dump some parts from the
> > backup and replay it against a fresh database. I'm interested only in
> > contacts and messages; as far as I can tell everything else has a
> > "data" counterpart that's reindexed. Which tables do I need to dump
> > for that?
>
> No. And I know this sucks. Sorry.
>
>
> > Thanks,
> > JÄnis
> > _______________________________________________
> > tracker-list mailing list
> > tracker-list gnome org
> > https://mail.gnome.org/mailman/listinfo/tracker-list

-- 


Philip Van Hoof
Software developer
Codeminded BVBA - http://codeminded.be