diff --git a/hive/db/schema.py b/hive/db/schema.py
index d58d383b7ac455098bcff191c36d643093d03b50..75cafd4f6e386c34e26aa1e5e1f3cfb6edad35e6 100644
--- a/hive/db/schema.py
+++ b/hive/db/schema.py
@@ -220,6 +220,7 @@ def build_metadata():
         'hive_post_tags', metadata,
         sa.Column('post_id', sa.Integer, nullable=False),
         sa.Column('tag_id', sa.Integer, nullable=False),
+        sa.PrimaryKeyConstraint('post_id', 'tag_id', name='hive_post_tags_pk1'),
         sa.ForeignKeyConstraint(['post_id'], ['hive_posts.id']),
         sa.ForeignKeyConstraint(['tag_id'], ['hive_tag_data.id']),
     )