psycopg is a PostgreSQL database adapter for the Python programming
language. It was written from scratch with the aim of being very small and
fast, and stable as a rock. The main advantages of psycopg are that it
supports the full Python DBAPI-2.0 and being thread safe at level 2.

psycopg is different from the other database adapter because it was designed
for heavily multi-threaded applications that create and destroy lots of
cursors and make a conspicuous number of concurrent INSERTs or UPDATEs.
Every open Python connection keeps a pool of real (UNIX or TCP/IP)
connections to the database. Every time a new cursor is created, a new
connection does not need to be opened; instead one of the unused connections
from the pool is used. That makes psycopg very fast in typical client-server
applications that create a servicing thread every time a client request
arrives.

WWW: http://initd.org/software/psycopg