python-cx_Oracle/samples/QueryChangeNotification.py

61 lines
2.4 KiB
Python

#------------------------------------------------------------------------------
# Copyright 2016, 2017, Oracle and/or its affiliates. All rights reserved.
#
# Portions Copyright 2007-2015, Anthony Tuininga. All rights reserved.
#
# Portions Copyright 2001-2007, Computronix (Canada) Ltd., Edmonton, Alberta,
# Canada. All rights reserved.
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# QueryChangeNotification.py
# This script demonstrates using query change notification in Python, a
# feature that is available in Oracle 11g. Once this script is running, use
# another session to insert, update or delete rows from the table
# cx_Oracle.TestTempTable and you will see the notification of that change.
#------------------------------------------------------------------------------
from __future__ import print_function
import cx_Oracle
import threading
import time
def callback(message):
print("Message type:", message.type)
print("Message database name:", message.dbname)
print("Message queries:")
for query in message.queries:
print("--> Query ID:", query.id)
print("--> Query Operation:", query.operation)
for table in query.tables:
print("--> --> Table Name:", table.name)
print("--> --> Table Operation:", table.operation)
if table.rows is not None:
print("--> --> Table Rows:")
for row in table.rows:
print("--> --> --> Row RowId:", row.rowid)
print("--> --> --> Row Operation:", row.operation)
print("-" * 60)
print("=" * 60)
connection = cx_Oracle.Connection("cx_Oracle/dev@localhost/orcl",
events = True)
sub = connection.subscribe(callback = callback, timeout = 1800,
qos = cx_Oracle.SUBSCR_QOS_QUERY | cx_Oracle.SUBSCR_QOS_ROWIDS)
print("Subscription:", sub)
print("--> Connection:", sub.connection)
print("--> Callback:", sub.callback)
print("--> Namespace:", sub.namespace)
print("--> Protocol:", sub.protocol)
print("--> Timeout:", sub.timeout)
print("--> Operations:", sub.operations)
print("--> Rowids?:", bool(sub.qos & cx_Oracle.SUBSCR_QOS_ROWIDS))
queryId = sub.registerquery("select * from TestTempTable")
print("Registered query:", queryId)
while True:
print("Waiting for notifications....")
time.sleep(5)