Re: Consecutive Inserts Freeze Execution of Psycopg3 - Mailing list psycopg
| From | Michael P. McDonnell |
|---|---|
| Subject | Re: Consecutive Inserts Freeze Execution of Psycopg3 |
| Date | |
| Msg-id | CAHmCLHrrT5geecTN1LbkJbvQdA6XhU4gW7bsroRtMEMfLY0aPw@mail.gmail.com Whole thread Raw |
| In response to | Consecutive Inserts Freeze Execution of Psycopg3 ("Michael P. McDonnell" <bzaks1424@gmail.com>) |
| Responses |
Re: Consecutive Inserts Freeze Execution of Psycopg3
(Adrian Klaver <adrian.klaver@aklaver.com>)
|
| List | psycopg |
So I appreciate you're trying to point to the official source of the documentation; but one place where FastAPI might be a place of inspiration is the consistent building of a single use case example to show how one might do something more complex. Given the docs available - I have no idea how I might take a dict and generate an UPDATE statement using the sql.SQL API you have.
And I'm genuinely not trying to nitpick here, I'm relatively new to Python and am more or less winging it and the documentation immediately available doesn't exactly spell out *all the things*; So again - thank you for your help in getting me over the original hump; I appreciate it.
On Sun, Apr 23, 2023 at 7:59 PM Adrian Klaver <adrian.klaver@aklaver.com> wrote:
On 4/23/23 17:26, Michael P. McDonnell wrote:
> Thanks Adrian -
> I appreciate it; and I've been pouring through documentation to try and
> get to this point.
> I can't help but feel I'm doing it "wrong" but no website I can find
> recently seems to have a "right" way of doing things that's reasonably
> kept up.
> It would be nice if "wrong" had a way of shooting me in the foot with
> verbose errors or warnings.
Start here:
https://www.psycopg.org/psycopg3/docs/basic/index.html
and work through the sections in order.
>
> -Mike
>
> On Sun, Apr 23, 2023 at 7:15 PM Adrian Klaver <adrian.klaver@aklaver.com
> <mailto:adrian.klaver@aklaver.com>> wrote:
>
> On 4/23/23 14:55, Michael P. McDonnell wrote:
> > That helped a ton, I don't understand why I've had to rewrite the
> crap
> > out of all of this to get it to work (dropping SqlAlchemy, upgrading
> > from psycopg2 to psycopg, etc...) but it's working now and I can
> work
> > around it. Thank you.
>
> Well:
>
> 1) SQLAlchemy is an ORM that tries to make all databases look the same.
>
> 2) psycopg2 != psycopg. For details see:
>
> https://www.psycopg.org/psycopg3/docs/basic/from_pg2.html
> <https://www.psycopg.org/psycopg3/docs/basic/from_pg2.html>
>
> 3) It would have been more of a surprise if you did not have to change
> anything.
>
> 4) And this
>
> with self.connection.cursor() as conn:
>
> was just plain wrong. You where trying to make a cursor be a connection
> and that is not going to work.
>
>
> >
> >
> > On Sun, Apr 23, 2023 at 4:25 PM Adrian Klaver
> <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
> > <mailto:adrian.klaver@aklaver.com
> <mailto:adrian.klaver@aklaver.com>>> wrote:
> >
> > On 4/23/23 13:45, Michael P. McDonnell wrote:
> > > Python 3.10.6
> > > psycopg library 3.1.8
> > >
> > > Running consecutive inserts sourced in files.
> > > All inserts are of the same format:
> > >
> > > INSERT INTO _____ (field1, field2, field3)
> > > SELECT field1, field2, field3 FROM ____, Join ___, join
> ___ etc...
> > >
> > > The code I've written is this:
> > >
> > > for qi in range(qlen):
> > > query = queries[qi]
> > > qparams = params[qi]
> > > with self.connection.cursor() as conn:
> > > conn.execute(query, qparams)
> >
> > In above you are running the context manager(with) over the
> cursor not
> > the connection. This will not automatically commit the
> transaction. You
> > will need to either explicitly do connection.commit() or use
> the with
> > over the connection per:
> >
> > https://www.psycopg.org/psycopg3/docs/basic/transactions.html
> <https://www.psycopg.org/psycopg3/docs/basic/transactions.html>
> >
> <https://www.psycopg.org/psycopg3/docs/basic/transactions.html
> <https://www.psycopg.org/psycopg3/docs/basic/transactions.html>>
> >
> > >
> > > When I run the queries in dbeaver - the first query takes
> 120s (it's
> > > 1.9M rows), the second query takes 2s (7000 rows).
> > > When I run the queries in python - it freezes on the
> second query.
> > >
> > > Any guidance on how to attack this would be awesome as I have
> > re-written
> > > my code a dozen times and am just slinging mud to see what
> sticks.
> >
> > --
> > Adrian Klaver
> > adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
> <mailto:adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>>
> >
>
> --
> Adrian Klaver
> adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
>
--
Adrian Klaver
adrian.klaver@aklaver.com