Cannot import sqlite3 in Python3

Question

I am unable to import the sqlite3 module in Python, version 3.5.0. Here's what I get:

>>> import sqlite3
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.5/sqlite3/__init__.py", line 23, in <module>
    from sqlite3.dbapi2 import *
  File "/usr/local/lib/python3.5/sqlite3/dbapi2.py", line 27, in <module>
    from _sqlite3 import *
ImportError: No module named '_sqlite3'

I know, I know, there are PLENTY of StackOverflow posts and support forums across the web where people complain about this problem, but none of the posted solutions have worked for me so far. Here's where I've been:

1. I also have Python 2.6.6 installed on this server, which is running CentOS 6.8 x86_64. I can open up the Python REPL and import sqlite3 just fine when using Python 2.6.6. I can also use sqlite3 from straight from bash and nothing seems awry.

2. This helpful question looked promising. I tried to re-configure and re-compile Python3.5 with the --enable-loadable-sqlite-extensions option, as user jammyWolf suggested. Nope, same error still occurs.

3. I've been using virtual environments like a good boy, but I have root access to this server. So, I was a bad boy and ran python3 as root without any virtualenvs activated. Still no luck. So I don't think it has anything to do with permissions.

4. I noticed that in the error message, it says No module named '_sqlite3'. This thread suggests that the underscore before the module name means that the module is an implementation detail, and isn't exposed in the API. ... I'm not sure what to make of this information, but there may be a hint somewhere in there.

Any ideas?

Actinium

sqlite3 is Python code; _sqlite3 is C code. The original Python of your distribution should already have included the SQLite library. Did you compile 3.5 yourself? – Stewpan

Yes, I did compile Python 3.5 myself. If I try to recompile it, is there a particular flag or something I should be aware of? (Also, I had no idea _sqlite3 was C code; thanks for that!) – Actinium

Isn't there some 3.5 package for your distribution? Anyway, your question actually is about how to compile Python correctly; edit it. – Stewpan

@CL., Installing python package could install sqlite library package (.so) as a dependency, but not header, library (.h, .a, ..., included in sqlite development package) which is required when compiling python extension module. – Hexaemeron

Can be of interest that on ubuntu one would install sqlite-devel with: sudo apt-get install libsqlite3-dev. Configuration of python compilation is the same (./configure --enable-loadable-sqlite-extensions). – Ediva

Answer 1

Falsetru is correct, I am going to go into a bit more detail for those not familiar (linux instructions). If you are getting this error, chances are you are using a version of python that was compiled without the correct headers. Here's a step by step guide to get it sorted. (Python 3.X.X instructions)

1. Install the required sqlite libraries

   sudo apt-get install libsqlite3-dev 

2. Uninstall python (I'm using python 3.6.5 as an example in this guide)

   sudo apt-get remove python3.6

3. Download python from source

   cd /tmp && wget https://www.python.org/ftp/python/3.6.5/Python-3.6.5.tgz

4. Unpack the archive

   tar -xvf Python-3.6.5.tgz

5. Configure

   cd Python-3.6.5 && ./configure

6. Make and install (and go make coffee while you're at it)

   make && sudo make install

If you did everything correctly running "python3.6 -V" should give you your python version. Note you will have to rebuild any virtual environments you have as well.

One final caveat you may encounter.

zipimport.ZipImportError: can't decompress data; zlib not available

This happens if you don't have the following zlib library installed:

sudo apt-get install zlib1g-dev

Gillespie

Answer 2

Install sqlite-devel package which includes header, library that is required to build sqlite3 extension.

yum install sqlite-devel

NOTE: Python does not include sqlite3 library itself, but an extension module (wrapper).

Hexaemeron

Ah, I should have mentioned that I tried that. I'm getting No package sqlite-devel available. – Actinium

@fterdal, Try yum list | grep sqlite | grep dev. It will list sqlite development package; then install that package instead of sqlite-devel. – Hexaemeron

Python has its own copy of the SQLite library; a separate package is not needed. – Stewpan

@CL., Do you mean this? hg.python.org/cpython/file/tip/Modules/_sqlite It's not an sqlite3 library itself, but a python extension that uses sqlite3 library. – Hexaemeron

Answer 3

I copied sqlite3.dll to this folder:

C:\Users\*****\Anaconda3\DLLs

It worked after two weeks trying everything else.

Neelon

Answer 4

For those facing this issue, Python's Dev Guide says: *For Unix-based systems, we try to use system libraries whenever available. This means optional components will only build if the relevant system headers are available. *.

https://devguide.python.org/getting-started/setup-building/#install-dependencies

In fact, I was facing the very same issue on my Ubuntu distro with sqlite3 and tkinter modules, which were both solved when I installed the dependencies specified in the document, which are (change apt-get according to your distro):

sudo apt-get install build-essential gdb lcov pkg-config
libbz2-dev libffi-dev libgdbm-dev libgdbm-compat-dev liblzma-dev
libncurses5-dev libreadline6-dev libsqlite3-dev libssl-dev
lzma lzma-dev tk-dev uuid-dev zlib1g-dev

By installing all of them and recompilling the source, everything worked fine.

Danielldaniella