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#------------------------------------------------------------------------------
# Copyright (c) 2016, 2021, 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.
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# type_handlers.py
# This script demonstrates the use of input and output type handlers as well
# as variable input and output converters. These methods can be used to extend
# cx_Oracle in many ways. This script demonstrates the binding and querying of
# SQL objects as Python objects.
#
# This script requires cx_Oracle 5.0 and higher.
#------------------------------------------------------------------------------
import datetime
import cx_Oracle as oracledb
import sample_env
con = oracledb.connect(sample_env.get_main_connect_string())
obj_type = con.gettype("UDT_BUILDING")
class Building:
def __init__(self, building_id, description, num_floors, date_built):
self.building_id = building_id
self.description = description
self.num_floors = num_floors
self.date_built = date_built
def __repr__(self):
return "<Building %s: %s>" % (self.building_id, self.description)
def building_in_converter(value):
obj = obj_type.newobject()
obj.BUILDINGID = value.building_id
obj.DESCRIPTION = value.description
obj.NUMFLOORS = value.num_floors
obj.DATEBUILT = value.date_built
return obj
def building_out_converter(obj):
return Building(int(obj.BUILDINGID), obj.DESCRIPTION, int(obj.NUMFLOORS),
obj.DATEBUILT)
def input_type_handler(cursor, value, num_elements):
if isinstance(value, Building):
return cursor.var(obj_type, arraysize=num_elements,
inconverter=building_in_converter)
def output_type_handler(cursor, name, default_type, size, precision, scale):
if default_type == oracledb.OBJECT:
return cursor.var(obj_type, arraysize=cursor.arraysize,
outconverter=building_out_converter)
buildings = [
Building(1, "The First Building", 5, datetime.date(2007, 5, 18)),
Building(2, "The Second Building", 87, datetime.date(2010, 2, 7)),
Building(3, "The Third Building", 12, datetime.date(2005, 6, 19)),
]
cur = con.cursor()
cur.inputtypehandler = input_type_handler
for building in buildings:
try:
cur.execute("insert into TestBuildings values (:1, :2)",
(building.building_id, building))
except oracledb.DatabaseError as e:
error, = e.args
print("CONTEXT:", error.context)
print("MESSAGE:", error.message)
raise
print("NO OUTPUT TYPE HANDLER:")
for row in cur.execute("select * from TestBuildings order by BuildingId"):
print(row)
print()
cur = con.cursor()
cur.outputtypehandler = output_type_handler
print("WITH OUTPUT TYPE HANDLER:")
for row in cur.execute("select * from TestBuildings order by BuildingId"):
print(row)
print()
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