PostgreSQL, Second Edition

Client 1—Connecting to the Server

To interact with a PostgreSQL server using Python's DB-API, you must first import the pgdb module. This module defines a few exception classes (we'll talk about exceptions a little later), two classes (pgdbCnx and pgdbCursor), and a single module function.

The pgdb.connect() function returns a connection object (an instance of class pgdbCnx). This function actually comes in two flavors:

pgdb.connect( dsn )
pgdb.connect( dsn      = dsn, 
              user     = user, 
              password = password, 
              host     = host, 
              database = dbname )

In the first flavor, the dsn is expected to be a string of the form:

host:database:user:password:opt:tty

The rules for composing a valid dsn are a bit complex. In the simplest case, you can specify all connection ...