I wrote last week about
Kobo e-reader's sqlite database by hand.
But who wants to remember all the table names and type out those queries?
I sure don't. So I wrote a Python wrapper that makes it much easier to
interact with the Kobo databases.
Happily, Python already has a module called sqlite3.
So all I had to do was come up with an API that included the calls
I typically wanted -- list all the books, list all the shelves,
figure out which books are on which shelves, and so forth.
The result was
which includes a main function that can list books, shelves, or shelf contents.
You can initialize kobo_utils like this:
koboDB = KoboDB("/path/where/your/kobo/is/mounted")
throws an exception if it can't find the
Then you can list books thusly:
or list shelf names:
which books are on which shelves:
shelves = koboDB.get_dlist("Shelf", selectors=[ "Name" ])
for shelf in shelves:
What I really wanted, though, was a way to organize my library,
taking the tags in each of my epub books and assigning them to
an appropriate shelf on the Kobo, creating new shelves as needed.
Using kobo_utils.py plus the
epub library I'd already written, that ended up being quite
[ 20:38 Sep 15, 2015
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I've been enjoying reading my new Kobo Touch quite a lot. The screen
is crisp, clear and quite a bit whiter than my old Nook;
the form factor is great, it's reasonably responsive (though there
are a few places on the screen where I have to tap harder than other
places to get it to turn the page), and I'm happy with the choice of fonts.
But as I mentioned in my
previous Kobo article,
there were a few tweaks I wanted to make; and I was very happy with how
easy it was to tweak, compared to the Nook. Here's how.
Mount the Kobo
When you plug the Kobo in to USB, it automatically shows up as a
USB-Storage device once you tap "Connect" on the Kobo -- or as two
storage devices, if you have an SD card inserted.
Like the Nook, the Kobo's storage devices show up without partitions.
For instance, on Linux, they might be /dev/sdb and /dev/sdc, rather
than /dev/sdb1 and /dev/sdc1. That means they also don't present UUIDs
until after they're already mounted, so it's hard to make an entry for
them in /etc/fstab if you're the sort of dinosaur (like I am) who prefers
that to automounters.
Instead, you can use the entry in /dev/disk/by-id.
So fstab entries, if you're inclined to make them, might look like:
/dev/disk/by-id/usb-Kobo_eReader-3.16.0_N905K138254971:0 /kobo vfat user,noauto,exec,fmask=133,shortname=lower 0 0
/dev/disk/by-id/usb-Kobo_eReader-3.16.0_N905K138254971:1 /kobosd vfat user,noauto,exec,fmask=133,shortname=lower 0 0
One other complication, for me, was that the Kobo is one of a few
devices that don't work through my USB2 powered hub. Initially I
thought the Kobo wasn't working, until I tried a cable plugged
directly into my computer. I have no idea what controls which devices
work through the hub and which ones don't.
(The Kobo also doesn't give any indication when it's plugged in to a
wall charger, nor does
The sqlite database
Once the Kobo is mouted,
ls -a will show a directory
named .kobo. That's where all the good stuff is:
in particular, KoboReader.sqlite, the device's database,
and Kobo/Kobo eReader.conf, a human-readable configuration file.
Browse through Kobo/Kobo eReader.conf for your own amusement,
but the remainder of this article will be about KoboReader.sqlite.
I hadn't used sqlite before, and I'm certainly no SQL expert. But a
little web searching and experimentation taught me what I needed to know.
First, make a local copy of KoboReader.sqlite, so you don't risk
overwriting something important during your experimentation.
The Kobo is apparently good at regenerating data it needs, but
you might lose information on books you're reading.
To explore the database manually, run:
Some useful queries
Here are some useful sqlite commands, which you can generalize to
whatever you want to search for on your own Kobo. Every query (not .tables)
must end with a semicolon.
Show all tables in the database:
The most important ones, at least to me, are content (all your books),
Shelf (a list of your shelves/collections), and ShelfContent
(the table that assigns books to shelves).
Show all column names in a table:
There are a lot of columns in content
, so try
to see a much simpler table.
Show the names of all your shelves/collections:
SELECT Name FROM Shelf;
Show everything in a table:
SELECT * FROM Shelf;
Show all books assigned to shelves, and which shelves they're on:
SELECT ShelfName,ContentId FROM ShelfContent;
ContentId can be a URL to a sideloaded book, like
, or a UUID like
de98dbf6-e798-4de2-91fc-4be2723d952f for books from the Kobo store.
Show all books you have installed:
SELECT Title,Attribution,ContentID FROM content WHERE BookTitle is null ORDER BY Title;
One peculiarity of Kobo's database: each book has lots of entries,
apparently one for each chapter. The entries for chapters have the
chapter name as Title, and the book title as BookTitle. The entry
for the book as a whole has BookTitle empty, and the book title as Title.
For example, I have file:///mnt/sd/earnest.epub
sqlite> SELECT Title,BookTitle from content WHERE ContentID LIKE "%hamlet%";
HAMLET, PRINCE OF DENMARK|Hamlet
Scene II. Elsinore. A room of state in the Castle.|Hamlet
Scene III. A room in Polonius's house.|Hamlet
Scene IV. The platform.|Hamlet
Scene V. A more remote part of the Castle.|Hamlet
[ ... and so on ... ]
Scene II. A hall in the Castle.|Hamlet
Each of these entries has Title set to the name of the chapter (an act
in the play) and BookTitle set to Hamlet
, except for the final
entry, which has Title set to Hamlet
and BookTitle set to nothing.
That's why you need that query WHERE BookTitle is null
just want a list of your books.
Show all books by an author:
SELECT Title,Attribution,ContentID FROM content WHERE BookTitle is null
AND Attribution LIKE "%twain%" ORDER BY Title;
is where the author's name goes. LIKE %% searches
are case insensitive.
Of course, it's a lot handier to have a program that knows these queries
so you don't have to type them in every time (especially since the sqlite3
app has no history or proper command-line editing).
But this has gotten long enough, so I'll write about that separately.
[ 19:11 Sep 03, 2015
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I've been learning CouchDB, the hot NoSQL database, as part of my
new job. It's interesting -- a very different mindset compared to
classic databases like MySQL.
There's a fairly good Python package for it, python-couchdb ...
but the documentation is somewhat incomplete and there's very little
else written about it, and virtually no sample code to steal.
That makes it a perfect topic for a Linux Planet tutorial!
So here it is, Part 1:
on a Couch! Using Python with CouchDB.
I have a rather fun application for the database I introduce in the
article, but you'll have to wait until Part 2, two weeks from now,
to see the details.
[ 11:55 Sep 23, 2010
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