can change storage with set_storage, storage's name is store in storage object and storage is create with get_storage

tiramisu/storage/dictionary/storage.py

@@ -24,6 +24,8 @@ from tiramisu.i18n import _
 
 class Storage(object):
     __slots__ = tuple()
+    storage = 'dictionary'
+
     def __init__(self, config_id, is_persistent):
         if is_persistent:
             raise ValueError(_('a dictionary cannot be persistent'))

tiramisu/storage/sqlite3/storage.py

@@ -25,6 +25,7 @@ import sqlite3
 
 class Storage(object):
     __slots__ = ('_conn', '_cursor', 'is_persistent', 'db_file')
+    storage = 'sqlite3'
 
     def __init__(self, config_id, is_persistent):
         self.is_persistent = is_persistent

tiramisu/storage/sqlite3/value.py

@@ -70,12 +70,12 @@ class Values(Cache):
         path = self._sqlite_encode_path(path)
         self.storage.execute("DELETE FROM value WHERE path = ?", (path,))
 
-    def get_modified_values(self, context):
+    def get_modified_values(self):
         """return all values in a dictionary
         example: {option1: (owner, 'value1'), option2: (owner, 'value2')}
         """
         ret = {}
-        for path, value, owner in self.storage.select("SELECT value",
+        for path, value, owner in self.storage.select("SELECT * FROM value",
                                                       only_one=False):
             path = self._sqlite_decode_path(path)
             owner = getattr(owners, owner)