'''
    psycopg2-test.py
    Jeff Ondich, 1 Oct 2013

    This is a short example of how to access a PostgreSQL database in Python.
'''
    
import psycopg2 
import getpass 

# Get the database login info
database = 'your_user_name'
user = 'your_user_name'
password = getpass.getpass()

# Login to the database
try:
    connection = psycopg2.connect(database=database, user=user, password=password)
except Exception, e:
    print 'Connection error: ', e
    exit()

# Query the database
try:
    cursor = connection.cursor()
    query = 'SELECT city, population FROM populations WHERE year = 1950 ORDER BY population DESC LIMIT 10'
    cursor.execute(query)
    for row in cursor.fetchall():
        print row

    # An alternative to "for row in cursor.fetchall()" is "for row in cursor". The former
    # brings all the data into memory in your program, while the latter brings data in
    # small pieces (one row at a time, I think, but I haven't verified it yet).

except Exception, e:
    print 'Cursor error', e    
    connection.close()
    exit()

connection.close()