问题:

I'm guessing this is a pretty basic question, but I can't figure out why:

import psycopg2
psycopg2.connect("postgresql://postgres:postgres@localhost/postgres")

Is giving the following error:

psycopg2.OperationalError: missing "=" after
"postgresql://postgres:postgres@localhost/postgres" in connection info string

Any idea? According to the docs about connection strings I believe it should work, however it only does like this:

psycopg2.connect("host=localhost user=postgres password=postgres dbname=postgres")

I'm using the latest psycopg2 version on Python2.7.3 on Ubuntu12.04

回答1:

The connection string passed to psycopg2.connect is not parsed by psycopg2: it is passed verbatim to libpq. Support for connection URIs was added in PostgreSQL 9.2.

回答2:

I would use the urlparse module to parse the url and then use the result in the connection method. This way it's possible to overcome the psycop2 problem.

import urlparse # for python 3+ use: from urllib.parse import urlparse
result = urlparse.urlparse("postgresql://postgres:postgres@localhost/postgres")
username = result.username
password = result.password
database = result.path[1:]
hostname = result.hostname
connection = psycopg2.connect(
    database = database,
    user = username,
    password = password,
    host = hostname
)