diff --git a/hsdbi/mongo.py b/hsdbi/mongo.py
index 470f1a8..86a4de7 100644
--- a/hsdbi/mongo.py
+++ b/hsdbi/mongo.py
@@ -179,7 +179,10 @@ def all(self, projection=None):
         Returns:
           pymongo.cursor.Cursor with results.
         """
-        return self._collection.find({}, projection_dict(projection))
+        if projection:
+            return self._collection.find({}, projection_dict(projection))
+        else:
+            return self._collection.find()
 
     def commit(self):
         """Does nothing for a MongoRepository."""
@@ -248,9 +251,12 @@ def get(self, expect=True, projection=None, **kwargs):
           NotFoundError: if the item is not found in the database, but it is
             expected.
         """
-        item = next(self._collection.find(kwargs,
-                                          projection_dict(projection)),
-                    None)
+        if projection:
+            item = next(self._collection.find(kwargs,
+                                              projection_dict(projection)),
+                        None)
+        else:
+            item = next(self._collection.find(kwargs), None)
         if not item and expect:
             raise errors.NotFoundError(pk=kwargs, table=self._collection_name)
         return item
@@ -268,4 +274,19 @@ def search(self, projection=None, **kwargs):
         Returns:
           pymongo.cursor.Cursor with matching results (if any).
         """
-        return self._collection.find(kwargs, projection_dict(projection))
+        if projection:
+            return self._collection.find(kwargs, projection_dict(projection))
+        else:
+            return self._collection.find(kwargs)
+
+    def update(self, doc):
+        """Update the doc, saving attribute states into the db.
+
+        Args:
+          doc: the document to update.
+        """
+        _id = doc['_id']
+        doc.pop('_id')
+        self._collection.update_one(
+            {'_id': _id}, {'$set': doc})
+        doc['_id'] = _id
diff --git a/setup.py b/setup.py
index 0c3f51c..0cc0c76 100644
--- a/setup.py
+++ b/setup.py
@@ -7,12 +7,12 @@
 setup(
     name='hsdbi',
     packages=find_packages(exclude=['testing']),
-    version='0.1a12',
+    version='0.1a13',
     description='A simple interface for accessing databases.',
     author='Tim Niven',
     author_email='tim.niven.public@gmail.com',
     url='https://github.com/timniven/hsdbi',
-    download_url='https://github.com/timniven/hsdbi/archive/0.1a12.tar.gz',
+    download_url='https://github.com/timniven/hsdbi/archive/0.1a13.tar.gz',
     license='MIT',
     classifiers=[
         'Development Status :: 3 - Alpha',
diff --git a/testing/tests.py b/testing/tests.py
index 1578924..6cbd4f6 100644
--- a/testing/tests.py
+++ b/testing/tests.py
@@ -281,14 +281,10 @@ def setUp(self):
             db=db,
             collection_name='foo')
         self.test_cases = [('ABC', 'abc'), ('DEF', 'def'), ('GHI', 'def')]
-        for test_case in self.test_cases:
-            if self.repository.exists(_id=test_case[0]):
-                self.repository.delete(_id=test_case[0])
+        self.repository.delete_all_records()
 
     def tearDown(self):
-        for test_case in self.test_cases:
-            if self.repository.exists(_id=test_case[0]):
-                self.repository.delete(_id=test_case[0])
+        self.repository.delete_all_records()
 
     def _insert_one(self):
         self.repository.add(_id='ABC', name='abc')
@@ -382,3 +378,12 @@ def test_search_with_projection(self):
         self.assertEqual(len(items[1]), 1)
         self.assertEqual(items[0]['_id'], 'DEF')
         self.assertEqual(items[1]['_id'], 'GHI')
+
+    def test_update(self):
+        self._insert_one()
+        doc = self.repository.get(_id='ABC')
+        doc['new_attr'] = 123
+        self.repository.update(doc)
+        doc2 = self.repository.get(_id='ABC')
+        self.assertEqual(doc2['new_attr'], 123)
+        self.assertEqual(doc2['_id'], doc['_id'])