drcp.py

#------------------------------------------------------------------------------
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# Portions Copyright 2007-2015, Anthony Tuininga. All rights reserved.
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# Canada. All rights reserved.
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# either license.
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# the following applies:
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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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# See the License for the specific language governing permissions and
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#------------------------------------------------------------------------------

#------------------------------------------------------------------------------
# drcp.py
#
# Demonstrates the use of Database Resident Connection Pooling (DRCP) which
# provides a connection pool in the database server, thereby reducing the cost
# of creating and tearing down client connections. The pool can be started and
# stopped in the database by issuing the following commands in SQL*Plus:
#
#   exec dbms_connection_pool.start_pool()
#   exec dbms_connection_pool.stop_pool()
#
# Statistics regarding the pool can be acquired from the following query:
#
#   select * from v$cpool_cc_stats;
#
# There is no difference in how a connection is used once it has been
# established.
#
# DRCP has most benefit when used in conjunction with a local connection pool,
# see the python-oracledb documentation.
#------------------------------------------------------------------------------

import oracledb
import sample_env

# determine whether to use python-oracledb thin mode or thick mode
if not sample_env.get_is_thin():
    oracledb.init_oracle_client(lib_dir=sample_env.get_oracle_client())

conn = oracledb.connect(sample_env.get_drcp_connect_string(),
                        cclass="PYCLASS", purity=oracledb.ATTR_PURITY_SELF)
cursor = conn.cursor()
print("Performing query using DRCP...")
for row in cursor.execute("select * from TestNumbers order by IntCol"):
    print(row)