diff -r 57b4279d8c4e -r 03e267d67478 app/django/db/__init__.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/db/__init__.py	Fri Jul 18 18:22:23 2008 +0000
@@ -0,0 +1,74 @@
+import os
+from django.conf import settings
+from django.core import signals
+from django.core.exceptions import ImproperlyConfigured
+from django.dispatch import dispatcher
+from django.utils.functional import curry
+
+__all__ = ('backend', 'connection', 'DatabaseError', 'IntegrityError')
+
+if not settings.DATABASE_ENGINE:
+    settings.DATABASE_ENGINE = 'dummy'
+
+try:
+    # Most of the time, the database backend will be one of the official
+    # backends that ships with Django, so look there first.
+    _import_path = 'django.db.backends.'
+    backend = __import__('%s%s.base' % (_import_path, settings.DATABASE_ENGINE), {}, {}, [''])
+    creation = __import__('%s%s.creation' % (_import_path, settings.DATABASE_ENGINE), {}, {}, [''])
+except ImportError, e:
+    # If the import failed, we might be looking for a database backend
+    # distributed external to Django. So we'll try that next.
+    try:
+        _import_path = ''
+        backend = __import__('%s.base' % settings.DATABASE_ENGINE, {}, {}, [''])
+        creation = __import__('%s.creation' % settings.DATABASE_ENGINE, {}, {}, [''])
+    except ImportError, e_user:
+        # The database backend wasn't found. Display a helpful error message
+        # listing all possible (built-in) database backends.
+        backend_dir = os.path.join(__path__[0], 'backends')
+        available_backends = [f for f in os.listdir(backend_dir) if not f.startswith('_') and not f.startswith('.') and not f.endswith('.py') and not f.endswith('.pyc')]
+        available_backends.sort()
+        if settings.DATABASE_ENGINE not in available_backends:
+            raise ImproperlyConfigured, "%r isn't an available database backend. Available options are: %s" % \
+                (settings.DATABASE_ENGINE, ", ".join(map(repr, available_backends)))
+        else:
+            raise # If there's some other error, this must be an error in Django itself.
+
+def _import_database_module(import_path='', module_name=''):
+    """Lazily import a database module when requested."""
+    return __import__('%s%s.%s' % (import_path, settings.DATABASE_ENGINE, module_name), {}, {}, [''])
+
+# We don't want to import the introspect module unless someone asks for it, so
+# lazily load it on demmand.
+get_introspection_module = curry(_import_database_module, _import_path, 'introspection')
+
+def get_creation_module():
+    return creation
+
+# We want runshell() to work the same way, but we have to treat it a
+# little differently (since it just runs instead of returning a module like
+# the above) and wrap the lazily-loaded runshell() method.
+runshell = lambda: _import_database_module(_import_path, "client").runshell()
+
+# Convenient aliases for backend bits.
+connection = backend.DatabaseWrapper(**settings.DATABASE_OPTIONS)
+DatabaseError = backend.DatabaseError
+IntegrityError = backend.IntegrityError
+
+# Register an event that closes the database connection
+# when a Django request is finished.
+dispatcher.connect(connection.close, signal=signals.request_finished)
+
+# Register an event that resets connection.queries
+# when a Django request is started.
+def reset_queries():
+    connection.queries = []
+dispatcher.connect(reset_queries, signal=signals.request_started)
+
+# Register an event that rolls back the connection
+# when a Django request has an exception.
+def _rollback_on_exception():
+    from django.db import transaction
+    transaction.rollback_unless_managed()
+dispatcher.connect(_rollback_on_exception, signal=signals.got_request_exception)