diff --git a/beets/library/models.py b/beets/library/models.py
index cbee2a411..f57b4201a 100644
--- a/beets/library/models.py
+++ b/beets/library/models.py
@@ -716,6 +716,7 @@ class Item(LibModel):
         "mtime": types.DATE,
         "added": types.DATE,
     }
+    _indices = (dbcore.Index("idx_item_album_id", ("album_id",)),)
 
     _search_fields = (
         "artist",