Adding the line

    features[0][0]

to the end of main() produces a segfault for me on Linux.

The FAQ for sqlite3 says that

    Under Unix, you should not carry an open SQLite database across a 
    fork() system call into the child process. Problems will result if 
    you do.

-- see http://www.sqlite.org/faq.html.  So assuming you are using Unix, this is probably not a Python bug.

(And anyway, I would not expect the pickling of row objects to work correctly.)