All local folders lost in KMail

[Peter Humphrey]

On Saturday, 17 August 2019 19:34:52 BST Martin Steigerwald wrote:
> Hi Peter.
> 
> Peter Humphrey - 17.08.19, 16:50:49 CEST:
> > > Akonadi misconception #1: where is my data?
> > > 
> > > https://blogs.kde.org/2011/11/13/akonadi-misconception-1-where-my-da
> > > ta
> > > 
> > > Which basically means that your mails could still be in the
> > > filesystem, somewhere under '~/.local/share' usually, where is
> > > somewhere would be 'local-mail' or 'akonadi_something_resource', at
> > > least for POP3. The resource configuration dialog in Akonadiconsole
> > > would tell the location. For IMAP they could theoretically still be
> > > on the IMAP server.
> > > 
> > > It is really important to understand that before claiming that mails
> > > may be lost. Of course mails disappearing from KMail for no good
> > > reason would still be a bug, but it might (!) not be a data loss.
> > > 
> > > 
> > > Some more of the information in such a data loss case would be:
> > > 
> > > 1) What does 'akonadictl fsck' tell?
> > 
> > Many thousands of "[...] has no RID", mostly Items, but also including
> > 20 Collections. (I stopped counting at 500 pages of 30.)  :)
> 
> Hmmm… that is a message about items Akonadi has in cache (i.e. database
> und file_db) but for some reasons did not manage to put into the remote
> location. For POP3 with Maildir resource this is the local maildir
> (~/.local/share/{local-mail|akonadi_maildir_resource_something}) and for
> IMAP this is the IMAP account.
> 
> Unfortunately Akonadi does not attempt a second time at the moment. This
> is one of the major changes Daniel still wanted to tackle, if I remember
> correctly.
> 
> I do have some of those as well and that is why I try to keep the
> database. I am not sure why Akonadi would ever fail to store a mail in
> the local maildir. However I am not sure whether in my case this would
> cause any data loss, I did not appear to loose anything as I migrated
> from MariaDB to PostgreSQL, basically by deleting the database (with a
> backup before) and letting it build a new one. At least I did not miss
> something.
> 
> But in your case when you get this many of those messages… there might
> be a hint on why or how you lost data.
> 
> One of the messages I got was:
> 
> Item "1467067" in collection "434" has no RID.
> 
> With some knowledge it is possible to trace this back to an item.
> 
> Collection is basically the folder the item is in. And the item refers
> to the actual item, like the mail, event, task or contact.
> 
> You can see the item IDs when opening a folder in the "Browser" tab of
> Akonadi console. I believe you can see the collection ID of a folder in
> the attributes window you can access with the context menu by right
> clicking on a folder in Akonadi Console. And I believe you can search
> within a table for collections what folder has what idea, but I do not
> know the actual SQL query.
> 
> And yes… IMHO the user should never have to deal with any of that but…
> if you again experience a mail loss, this knowledge might be helpful to
> find out what happened.

Many thanks Martin.

-- 
Regards,
Peter.

Gentoo stable system, openrc-0.41.2
gcc 8.3.0, sys-kernel/gentoo-sources 4.19.66
QT 5.12.3, KDE frameworks 5.60.0, KDE plasma 5.15.5
KDE apps 19.04.3 incl KMail 19.04.3 (5.11.3), akonadi 19.04.3
dev-db/mariadb-10.2.22-r1, net-libs/webkit-gtk-2.24.2
x11-drivers/xf86-video-amdgpu 19.0.1
dev-libs/amdgpu-pro-opencl 19.10.785425-r1