Question

I would like to create a :memory: database in python and access it from different threads.
Essentially something like:

class T(threading.Thread):
    def run(self):
        self.conn = sqlite3.connect(':memory:')
        # do stuff with the database

for i in xrange(N):
    T().start()

and have all the connections referring to the same database.

I am aware of passing check_same_thread=True to the connect function and sharing the
connection between threads but would like to avoid doing that if possible. Thanks for any help.

EDIT: corrected a typo. I originally said “have all the connections referring to the same thread” substituting thread for database.

Answer 1

Without hacking sqlite3 library itself you cannot reuse :memory: database, because it’s guaranteed to be exclusive and private for every connection. To hack access to it, look closer at src/pager.c in sqlite3 distribution (not Python module distribution). Maybe, most convenient way to implement this would be make :memory:00, :memory:something, :memory:okay_hai etc. aliases to address different pPager->memDb pointers through some simple C-side mapping.