two files needed for %pg magic in IPython - pgdb.py and pgmagic.py, this is pgmagic.py

gistfile1.py

__author__ = 'nitin'

# -*- coding: utf-8 -*-
"""
===========
pgmagic
===========

Magics for interacting with Postgres database server via psycopg2.

.. note::

  The ``psycopg2`` module needs to be installed separately and
  can be obtained using ``easy_install`` or ``pip``.

Usage
=====

``%pg_qry``

{PG_QRY_DOC}

``%pg_test``

{PG_TEST_DOC}

``%pg_close``

{PG_CLOSE_DOC}

"""

#-----------------------------------------------------------------------------
#  Copyright (C) 2012 Nitin Borwankar
#
#  Distributed under the terms of the BSD License.  The full license is in
#  the file COPYING, distributed as part of this software.
#-----------------------------------------------------------------------------


import pgdb

#from IPython.core.displaypub import publish_display_data
from IPython.core.magic import (Magics, magics_class, line_magic, line_cell_magic, needs_local_scope)
from IPython.testing.skipdoctest import skip_doctest
from IPython.core.magic_arguments import (argument, magic_arguments, parse_argstring)

from IPython.utils.py3compat import unicode_to_str


@magics_class
class PGMagics(Magics):
    """A set of magics useful for interactive work with Postgres server via psycopg2.
    """
    def __init__(self, shell, data):
        super(PGMagics, self).__init__(shell)
        self._pg = pgdb
        self._cs = self._pg.connect_string(self._pg.db_data)
        self._data = data
        # prints to console to let developer know alls well - debug use only
        print "PGMagics.__init__ got data: %s" % (data)

    @skip_doctest
    @line_magic
    def pg_test(self, line):
        return self._pg.test()

    @skip_doctest
    @line_cell_magic
    def pg_qry(self, line, cell=None, local_ns=None):

        print "line = %s" % (line)
        print "cell = %s" % (cell)

        #args = parse_argstring(self.pg_qry, line)
        #print "args: %s" % (args)
        # arguments 'code' in line are prepended to
        # the cell lines

        if cell is None:
            code = line
            return_output = True
            line_mode = True
        else:
            code = line + ' ' + cell
            return_output = False
            line_mode = False

        #code = ' '.join(args.code) + code

        print "line_mode = %s" % (line_mode)
        print "code = %s" % (code)

        text_output = ''
        if line_mode:
            for line in code.split(';'):
                status, results = self._pg.exec_qry(line)
                text_output += str(results)
        else:
            status, results = self._pg.exec_qry(code)
            text_output += str(results)

        if not text_output:
            text_output = 'fail: ' + str(status)
        return text_output

    @skip_doctest
    @line_magic
    def pg_close(self, line):
        self._pg.close()


def load_ipython_extension(ip):
    """Load the extension in IPython."""
    magics = PGMagics(ip, {"x": 1, "y": 2}) # dummy data dict passed for testing
    ip.register_magics(magics)

"""
def unload_ipython_extension(ip):
    pass

ip = get_ipython()
magics = PGMagics(ip, {"x": 1, "y": 2})
ip.register_magics(magics)
"""