query from postgresql using python as dictionary

Question

I'm using Python 2.7 and postgresql 9.1. Trying to get dictionary from query, I've tried the code as described here: http://wiki.postgresql.org/wiki/Using_psycopg2_with_PostgreSQL

import psycopg2
import psycopg2.extras
conn = psycopg2.connect("dbname=mydb host=localhost user=user password=password")
cur = conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
cur.execute ("select * from port")
type(cur.fetchall())

It is printing the next answer:

<type 'list'>

printing the item itself, show me that it is list. The excepted answer was dictionary.

Edit:

Trying the next:

ans = cur.fetchall()[0]
print ans
print type(ans)

returns

[288, 'T', 51, 1, 1, '192.168.39.188']
<type 'list'>

Answer 1

Tnx a lot Andrey Shokhin ,

full answer is:

#!/var/bin/python 
import psycopg2
import psycopg2.extras
conn = psycopg2.connect("dbname=uniart4_pr host=localhost user=user password=password")
cur = conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
cur.execute ("select * from port")
ans =cur.fetchall()
ans1 = []
for row in ans:
    ans1.append(dict(row))

print ans1  #actually it's return

Answer 2

It's normal: when you call .fetchall() method returns list of tuples. But if you write

type(cur.fetchone())

it will return only one tuple with type:

<class 'psycopg2.extras.DictRow'>

After this you can use it as list or like dictionary:

cur.execute('SELECT id, msg FROM table;')
rec = cur.fetchone()
print rec[0], rec['msg']

You can also use a simple cursor iterator:

res = [json.dumps(dict(record)) for record in cursor] # it calls .fetchone() in loop

Answer 3

Perhaps to optimize it further we can have

#!/var/bin/python 
import psycopg2
import psycopg2.extras

def get_dict_resultset(sql):
    conn = psycopg2.connect("dbname=pem host=localhost user=postgres password=Drupal#1008")
    cur = conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
    cur.execute (sql)
    ans =cur.fetchall()
    dict_result = []
    for row in ans:
        dict_result.append(dict(row))
    return dict_result

sql = """select * from tablename"""
return get_dict_resultset(sql)