Upgrade Python's sqlite3 on Debian

Question

I'm using Python 2.7.6 (default, Mar 22 2014, 22:59:56) [GCC 4.8.2] on linux2 on my Debian, and I'm usually using module sqlite3 without any problem.

I compiled a Sqlite extension spellfix, I get this error when loading it:

sqlite3.OperationalError: ./spellfix.so: undefined symbol: sqlite3_malloc64

I think it might be because the sqlite3 module is too old:

import sqlite3
print sqlite3.version          # 2.6.0
print sqlite3.sqlite_version   # 3.8.2

(On another machine where sqlite3.sqlite_version is 3.8.7.x the extension loads fine).

I tried:

pip install --upgrade pysqlite

but it's still the same: sqlite3.sqlite_version stays 3.8.2.

How to upgrade the Python sqlite3 module (which is built-in in the standard library)?

Answer 1

Here is a manual solution (NOT RECOMMENDED, but as I didn't find backports for libsqlite3 v3.23.1 for my Linux install, I tried this, and it worked):

1. Download from https://packages.debian.org/search?keywords=libsqlite3-0 a newer version. Here is a direct link:

   wget http://ftp.de.debian.org/debian/pool/main/s/sqlite3/libsqlite3-0_3.23.1-1_amd64.deb
   

2. Decompress the .deb in a temporary folder:

   mkdir tmp
   dpkg -x libsqlite3-0_3.23.1-1_amd64.deb tmp
   

   or

   mkdir tmp; cd tmp; ar x ../libsqlite3-0_3.23.1-1_amd64.deb; tar xvfJ data.tar.xz; cd ..
   

   then

   # keep the old one in case it wouldn't work!
   mv /usr/lib/x86_64-linux-gnu/libsqlite3.so.0.8.6 /usr/lib/x86_64-linux-gnu/libsqlite3.so.0.8.6.old   
   
   # copy the new one in the right place
   cp tmp/usr/lib/x86_64-linux-gnu/libsqlite3.so.0.8.6 /usr/lib/x86_64-linux-gnu/libsqlite3.so.0.8.6
   

3. It should work:

   python -c "import sqlite3; print sqlite3.sqlite_version"   # 3.23.1
   

Disclaimer: this is a bit hack-ish, but it works.

Answer 2

You are right in thinking that the version of sqlite3 causes the problem. sqlite_malloc64 was introduced with release 3.8.7.

Instead of trying to upgrade the Python sqlite3 module which may end up breaking your Python installation, I would suggest compiling the version of spellfix.c included with version 3.8.2.

You can find the source here: https://www.sqlite.org/src/tarball/27392118/SQLite-27392118.tar.gz

From there you can build the amalgamation with:

sh configure
make sqlite3.c

You will have sqlite3.h and sqlite3ext.h in the tsrc folder. Then compile the spellfix.c extension with:

gcc -g -fPIC -shared spellfix.c -I ../../tsrc -o spellfix.dll

And you should get a compatible spellfix.dll that runs with your version of sqlite3.