diff --git a/src/calibre/db/backend.py b/src/calibre/db/backend.py
index 0eb4eb1aa0..5c0ffcf022 100644
--- a/src/calibre/db/backend.py
+++ b/src/calibre/db/backend.py
@@ -32,7 +32,7 @@ from calibre.utils.magick.draw import save_cover_data_to
 from calibre.utils.formatter_functions import load_user_template_functions
 from calibre.db.tables import (OneToOneTable, ManyToOneTable, ManyToManyTable,
         SizeTable, FormatsTable, AuthorsTable, IdentifiersTable, PathTable,
-        CompositeTable, UUIDTable)
+        CompositeTable, UUIDTable, RatingTable)
 # }}}
 
 '''
@@ -702,14 +702,15 @@ class DB(object):
                 metadata['column'] = col
             tables[col] = (PathTable if col == 'path' else UUIDTable if col == 'uuid' else OneToOneTable)(col, metadata)
 
-        for col in ('series', 'publisher', 'rating'):
+        for col in ('series', 'publisher'):
             tables[col] = ManyToOneTable(col, self.field_metadata[col].copy())
 
-        for col in ('authors', 'tags', 'formats', 'identifiers', 'languages'):
+        for col in ('authors', 'tags', 'formats', 'identifiers', 'languages', 'rating'):
             cls = {
                     'authors':AuthorsTable,
                     'formats':FormatsTable,
                     'identifiers':IdentifiersTable,
+                    'rating':RatingTable,
                   }.get(col, ManyToManyTable)
             tables[col] = cls(col, self.field_metadata[col].copy())
 
diff --git a/src/calibre/db/tables.py b/src/calibre/db/tables.py
index 295558c313..d8b623b352 100644
--- a/src/calibre/db/tables.py
+++ b/src/calibre/db/tables.py
@@ -276,6 +276,20 @@ class ManyToOneTable(Table):
                 self.link_table, lcol, table), (existing_item, item_id, item_id))
         return affected_books, new_id
 
+class RatingTable(ManyToOneTable):
+
+    def read_id_maps(self, db):
+        ManyToOneTable.read_id_maps(self, db)
+        # Ensure there are no records with rating=0 in the table. These should
+        # be represented as rating:None instead.
+        bad_ids = {item_id for item_id, rating in self.id_map.iteritems() if rating == 0}
+        if bad_ids:
+            self.id_map = {item_id:rating for item_id, rating in self.id_map.iteritems() if rating != 0}
+            db.conn.executemany('DELETE FROM {0} WHERE {1}=?'.format(self.link_table, self.metadata['link_column']),
+                                tuple((x,) for x in bad_ids))
+            db.conn.execute('DELETE FROM {0} WHERE {1}=0'.format(
+                self.metadata['table'], self.metadata['column']))
+
 class ManyToManyTable(ManyToOneTable):
 
     '''