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I am working on python plugins for QGIS. I have my and files. I connected it to database using Connection class and under def __init__(self, uri=None) in file. I want to connect to database through file.I imported into But how to call def __init__(self, uri=None) of from I need to create instance of 'Connection' class in order to call def __init__(self, uri=None) method of in How do I go about it? file:

class Connection(DbConn.Connection):

def getTypeName(self):
    return 'postgis'

def getTypeNameString(self):
    return 'PostgreSQL'

def getProviderName(self):
    return 'postgres'

def getSettingsKey(self):
    return 'PostgreSQL'

def icon(self):
    return QIcon(":/icons/postgis_elephant.png")


def __init__(self, uri=None):

    DbConn.Connection.__init__(self, uri) =
    #self.port = uri.port()
    #self.dbname = uri.database()
    #self.user = uri.username()
    #self.passwd = uri.password() ='localhost' 
    self.port =5432 
    self.dbname ='ssss'
    self.user = 'j'
    self.passwd = 'jkj'

    if self.dbname == '' or self.dbname is None:
        self.dbname = self.user

        self.con = psycopg2.connect(self.con_info())
    except psycopg2.OperationalError, e:
        raise DbError(e)

    self.has_spatial = self.check_spatial()


    # a counter to ensure that the cursor will be unique
    self.last_cursor_id = 0
if __name__ == "__main__":
window = Connection()

and is:

import sys
import pdb

from PyQt4 import QtGui, QtCore
import psycopg2
import pprint

#from qgis.core import *
#from qgis.gui import *

import postgis

from DatabaseModel import TableItem, SchemaItem, DatabaseModel
import DbConnection

from ui.DlgQueryBuilder_ui import Ui_Dialog
from DlgDbError import DlgDbError

from QueryParser import QueryParser
from QueryManager import *

class DlgQueryBuilder(QDialog, Ui_Dialog):
    so on.....
share|improve this question
Can you post the relevant sections of your code in your question please. It's hard to understand how your code is written. – Nathan W Feb 8 '12 at 10:02
ok sure........ – Poonam Narvekar Feb 8 '12 at 10:24
up vote 1 down vote accepted

This should work:


import postgis
conn = postgis.Connection()


from postgis import Connection
conn = Connection()
share|improve this answer
thanx a lot:).. – Poonam Narvekar Feb 8 '12 at 12:28

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