Metadata-Version: 1.0
Name: django-oraclepool
Version: 0.9
Summary: django database backend that uses cx_Oracle session pooling for connections
Home-page: http://bitbucket.org/edcrewe/django-oraclepool
Author: Ed Crewe, Taras Halturin
Author-email: ed.crewe@bris.ac.uk
License: Apache
Description: ILRT Django Oracle pool
        =======================
        
        Ed Crewe, `IT Services R&D
        <http://www.bris.ac.uk/ilrt>`_ at University of Bristol, May 2012
        
        Packaged version of http://code.djangoproject.com/ticket/7732 by Taras Halturin
        django database backend that uses cx_Oracle session pooling for connections
        
        See http://bitbucket.org/edcrewe/django-oraclepool
        
        Original Code Modifications
        ---------------------------
        
        Pruned original ticket's base.py to just hold the pooling relevant code. 
        Using the standard Oracle connection for the rest of the database classes, 
        ie. operations, client and introspection. 
        
        Tested with django 1.1 to 1.4
        
        Extra features
        --------------
        
        - Added the pooling and logging parameters to the settings.
        
        - The connector uses the standard python logging model and caters for logging 
          full details of queries, either to a file log or appending them to the 
          bottom of the screen if the log level is DEBUG.
        
        - Added an option for running against existing (older) Oracle databases, ie those 
          which may not have unicode for character fields.
        
        - Option also allows running the tests against an existing database so that 
          running tests doesnt require database creation (oracle sys dba) rights.
        
        - Added a modification to the cursor to not parse parameters if not required.
        
        Why use it?
        -----------
        
        Perhaps due to our remotely distributed Oracle network taking a very long time 
        to establish connections, the use of cx_Oracle's session pooling for 
        connections provided a truely radical performance boost for requests 
        from 3-4 secs/req to 0.4 secs/req, so many times faster.   
        
        For single direct Oracle access it might still give a doubling of performance. 
        Install it and run the performance test to find out (see below).
        
        Installation
        ------------
        
        Download the egg (or use buildout) or download the tarball and extract it. 
        Then add /path/to/django-oraclepool to your python path.
        
        Specify DATABASE_ENGINE = 'oraclepool' instead of 'oracle' in your settings.  
        
        If you dont want to use the default extra database settings then the following defaults
        are used
        
        >>> EXTRAS = {'min':4,        # starting number of pooled connections
        ...           'max':8,         # maximum number of connections in the pool
        ...           'increment':1,   # increase by this amount when more are needed
        ...           'threaded':True, # server platform optimisation 
        ...           'timeout':600,   # connection timeout, 600 = 10 mins
        ...           'log':0,         # extra logging functionality turned on
        ...           'logfile':'',    # file system path to log file
        ...           'existing':''    # Type modifications for existing database and flag for tests
        ...           'session':[]     # Add session optimisations applied to each fresh connection, eg.
        ...                            #   alter session set cursor_sharing = similar;
        ...                            #   Enables use of bind variables assuming it isnt set at a system level 
        ...			       #   alter session set session_cached_cursors = 20;
        ...                            #   Allows cursor reuse between queries   
        ...            'like':'LIKE'   # Option instead of LIKEC default which can stop indexes being used
        ...            }
        
        Note that if you want sql logging to screen when in DEBUG mode then add 
        'oraclepool.log_sql.SQLLogMiddleware' to your MIDDLEWARE_CLASSES
        
        
        General Performance
        -------------------
        
        Initially after apache restart you will see the first few requests taking the same time as each 
        one initiates a new pooled connection. Then request speed should drop as it loses the Oracle 
        connection time.
        
        NB: Note that if you have PythonDebug On then the pool may get flushed much more regularly. 
        So you will often get the slower pool populating requests.
        
        Using mod_wsgi rather than mod_python may give a 25% added increase although this needs
        confirmation on a production instance.
        
        It should be remembered that there is also a very great deal of performance work that can be 
        done at the database level. I have posted a page with some of the tips and tricks for 
        improving database performance on my blog - http://python.blogs.ilrt.org/database-performance/
        
        Pooling alternatives
        --------------------
        
        Pyora pool
        
        Also tried out pyora pool see http://code.google.com/p/pyorapool
        but found increase was only around 90% and also had 
        issues with connection control and database edits failing.
        This also requires the whole architecture of a separate remote procedure call daemon 
        that holds the connection pool. Uneccesary here ... although useful
        for pooling across different applications, or multiple servers.
        
        ORM pools
        
        Usually ORMs have a generic pooling capability, unfortuately djangos only has a beta one 
        in development, unless you plugin another ORM, eg. http://www.sqlalchemy.org/ instead. 
        However that does require code rewriting.
        
        Having said that a generic ORM level pool is unlikely to perform as well as one at the 
        database connector level, which in turn is going to be less fast than one within the 
        database itself (see below).
        
        Tests
        -----
        
        The tests are run via separate test apps in the django-oraclepool folder.
        Some of these tests are derived from a set for http://code.google.com/p/django-mssql/
        
        They also include the option to run the test suite against an existing database for users who dont
        have full oracle dba rights on their test oracle servers. 
        
        The key extra tests are performance timings for running the test suite via the pooled oracle
        connection vs the standard one. Hopefully these timings should indicate whether using oraclepool is
        of value when using django with your oracle server network. 
        
        Run the tests by running django-oraclepool/tests/manage.py test 
        Or run individual tests by supplying there name, eg. manage.py test performance
        
        The performance test simulates a real environment by running up a number of connections
        as would exist with a production web server (the Apache2 default is 2 processes * 64 threads)
        whilst the test creates a maximum of only 32.
        In practise I found the actual performance improvement significantly greater than that indicated 
        by the doubling of speed that the multiple connections performance test gives. However that
        may not be the case dependent on your production oracle and web server environment.
        
        
        
        
        
        
        
        TODO
        ----
        
        - Oracle 11g has internal session pooling - DRCP - and cx_Oracle can use that for
          even better performance, so need to add appropriate modification to test whether 
          the database 11g or later, and use this feature in place of a cx_Oracle side pool.
          NB: requires cx_Oracle 5, see http://www.oracle.com/technology/pub/articles/tuininga-cx_oracle.html
        
        
        Changelog
        =========
        
        0.9 Django 1.4 compatibility fixes (2012-05-18)
        -----------------------------------------------
        
        - Fix database connection usage for django 1.4 compatibility 
          [Ed Crewe]
        - Fix tests/monkeypatch for performance and regression tests to work OK
          [Ed Crewe]
        - Add alias to pool to ensure each connection has its own pool
          [Marc Bee]
        
        0.8 Django 1.3 compatibility fixes (2011-04-08)
        -----------------------------------------------
        
        - Make self.features = DatabaseFeatures(self) to work with oracle connector change
        - Fix the timezone for the tests
        - Improve the error reporting if the connection fails due to wrong credentials etc.
        
        [Ed Crewe]
        
        0.7 - Oracle LIKEC performance work around and bug fixes (2010-09-20)
        ---------------------------------------------------------------------
        
        - Optional switch of use of LIKEC for LIKE since LIKEC ignores indexes in old Oracle
          so has much worse performance, see http://code.djangoproject.com/ticket/11017
        - Tested an application and the test suite with django 1.2.3 and python 2.6 
          [Ed Crewe]
        - Clean up raising of strings, required for python 2.6 or higher
          [Reinout van Rees]
        - Lost an indent along the way for log_sql append to screen
          [kylen]
        - Fix multiple pool creation bug under heavy initial load - with locking
          [Aa`Koshh]
        - Fix old settings style with django 1.1 python 
          [akhenakh]
        
        0.6 - Minor bugs and django 1.2 compatibility fixes (2010-06-18)
        ----------------------------------------------------------------
        
        - Use django 1.2 database settings format by default
        - Fix a bug with adding sql log to page when in DEBUG
        - Remove print statements where not critical failiure since they will cause one with wsgi
        - Drop homogeneous extra argument since unecessary and breaks if used with earlier cx_Oracle
        - Fix tests for earlier cx_Oracle
        - Remove unused separate class declaration for pools
        - Make sure all tests pass
        - Ensure default settings are picked up when using old format settings with 1.2 [Marc Bee]
        
          [Ed Crewe]
        
        0.5 - Fix logger bug and add session config (2010-02-19)
        --------------------------------------------------------
        
        - Fix a bug preventing the logger from being used
        - Make sure session settings are only set on connection creation not cursor use
        - Add a session list of sql lines for optionally setting session parameters
        - Wrap connection signal in try except for older django compatibility.
        
          [Ed Crewe]
        
        0.4 - Fix performance test (2010-01-29)
        ---------------------------------------
        
        - Whoops, I realised the performance test was underplaying the improvement due to a bug,
          it now gives the same performance for single connections (as expected) and 300% 
          improvement for multiple ones.
        - Added signal for connection 'creation' and fixed raise of unicode error
        
          [Ed Crewe]
        
        0.3 - Initial release (2010-01-28)
        ----------------------------------
        
        - Added test suite including performance test to demonstrate benefits
        - Tested and made compatible with django 1.2 (as well as django 1.1)
        - Cleaned up the code and factored out anything that wasnt specific to pooling,
          subclassing most components from the standard Oracle engine.
        - Modified logging options so DEBUG switches on log to screen and EXTRAS['log'] 
          switches logging to file option separately.
        
          [Ed Crewe]
        
        0.2 - Used for UoB student reps
        -------------------------------
        
        - Commented out debug print statements from DatabaseWrapper._cursor which broke install in wsgi
        - Added DatabaseWrapper.__init__ like the oracle backend with client, creation and introspection
          borrowed from it, since creation is expected in django 1.1.1 code.
        - Added default value of None for settings in DatabaseWrapper._cursor since this argument is not 
          expected in django 1.1.1 code.
        - Added DATABASE_EXTRAS dictionary to set all the session parameters from django config.
        - Added session pool settings report method, to check these.
        - Added python logger option and sql_log middleware
        
          [Ed Crewe]
        
        0.1 - Unreleased
        ----------------
        
        * Initial release - packaging of code from http://code.djangoproject.com/ticket/7732
         
          [Taras Halturin, et al.]
        
Keywords: django oracle connection pooling cx_Oracle
Platform: UNKNOWN
Classifier: Programming Language :: Python
Classifier: Framework :: Django
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Topic :: Software Development :: Libraries :: Python Modules
