diff --git a/data/model/repository.py b/data/model/repository.py
index 6b9ea7f39..b613cd152 100644
--- a/data/model/repository.py
+++ b/data/model/repository.py
@@ -49,7 +49,10 @@ def _purge_all_repository_tags(namespace_name, repository_name):
                              (namespace_name, repository_name))
 
   # Delete all manifests.
-  repo_tags = RepositoryTag.select().where(RepositoryTag.repository == repo.id)
+  repo_tags = list(RepositoryTag.select().where(RepositoryTag.repository == repo.id))
+  if not repo_tags:
+    return
+
   TagManifest.delete().where(TagManifest.tag << repo_tags).execute()
 
   # Delete all tags.