Skip to content
Permalink
Branch: master
Find file Copy path
Find file Copy path
1 contributor

Users who have contributed to this file

57 lines (42 sloc) 1.95 KB
#------------------------------------------------------------------------------
# Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# Subclassing.py
#
# Demonstrate how to subclass cx_Oracle connections and cursors in order to
# add additional functionality (like logging) or create specialized interfaces
# for paticular applications.
#------------------------------------------------------------------------------
from __future__ import print_function
import cx_Oracle
import SampleEnv
# sample subclassed connection which overrides the constructor (so no
# parameters are required) and the cursor() method (so that the subclassed
# cursor is returned instead of the default cursor implementation)
class Connection(cx_Oracle.Connection):
def __init__(self):
connectString = SampleEnv.GetMainConnectString()
print("CONNECT to database")
return super(Connection, self).__init__(connectString)
def cursor(self):
return Cursor(self)
# sample subclassed cursor which overrides the execute() and fetchone()
# methods in order to perform some simple logging
class Cursor(cx_Oracle.Cursor):
def execute(self, statement, args):
print("EXECUTE", statement)
print("ARGS:")
for argIndex, arg in enumerate(args):
print(" ", argIndex + 1, "=>", repr(arg))
return super(Cursor, self).execute(statement, args)
def fetchone(self):
print("FETCH ONE")
return super(Cursor, self).fetchone()
# create instances of the subclassed connection and cursor
connection = Connection()
cursor = connection.cursor()
# demonstrate that the subclassed connection and cursor are being used
cursor.execute("select count(*) from ChildTable where ParentId = :1", (30,))
count, = cursor.fetchone()
print("COUNT:", int(count))
You can’t perform that action at this time.