Chris Angelico <ros...@gmail.com> writes: > ... > When I advise my students on basic databasing concepts, I recommend > this structure: > > conn = psycopg2.connect(...) > > with conn, conn.cursor() as cur: > cur.execute(...) > > The transaction block should always start at the 'with' block and end > when it exits. As long as you never nest them (including calling other > database-using functions from inside that block), it's easy to reason > about the database units of work - they always correspond perfectly to > the code blocks.
In my context (web applications), I strongly discourage this use - at least when "conn" does not handle subtransactions properly. In a web application, the main transaction should in general be controlled at the request level: a request should either succeed as a whole or have no side effects whatsoever. This prohibits local (somewhere deep in a component) transaction control. -- https://mail.python.org/mailman/listinfo/python-list
