Commit ea85d430 authored by Russell Keith-Magee's avatar Russell Keith-Magee
Browse files

Fixed #14231 -- Added an index to the expire_date column on the Session model.... 

Fixed #14231 -- Added an index to the expire_date column on the Session model. Thanks to joeri for the report, via Frodo from Medid.

This won't affect any existing session tables; see the release notes for migration instructions.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14378 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 90ac0230

django/contrib/sessions/models.py

+1 −1
Original line number Diff line number Diff line
@@ -45,7 +45,7 @@ class Session(models.Model): 
    session_key = models.CharField(_('session key'), max_length=40,

                                   primary_key=True)

    session_data = models.TextField(_('session data'))

    expire_date = models.DateTimeField(_('expire date'))

    expire_date = models.DateTimeField(_('expire date'), db_index=True)

    objects = SessionManager()



    class Meta:

docs/releases/1.3.txt

+18 −0
Original line number Diff line number Diff line
@@ -165,6 +165,24 @@ To return to the previous rendering (without the ability to clear the 
            model = Document

            widgets = {'document': forms.FileInput}



New index on database session table

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



Prior to Django 1.3, the database table used by the database backend

for the :doc:`sessions </topics/http/sessions>` app had no index on

the ``expire_date`` column. As a result, date-based queries on the

session table -- such as the query that is needed to purge old

sessions -- would be very slow if there were lots of sessions.



If you have an existing project that is using the database session

backend, you don't have to do anything to accommodate this change.

However, you may get a significant performance boost if you manually

add the new index to the session table. The SQL that will add the

index can be found by running the :djadmin:`sqlindexes` admin

command::



    python manage.py sqlindexes sessions



.. _deprecated-features-1.3:



Features deprecated in 1.3