3 files changed, 25 insertions(+), 3 deletions(-)

A alembic/versions/ebbe2ad47fef_add_taggings_pkey.py
M stewdio/types/tag.py
M stewdio/types/tagging.py

@@ 0,0 1,22 @@
+"""add indexes
+
+Revision ID: ebbe2ad47fef
+Revises: bf4bf948f860
+Create Date: 2018-09-22 13:55:16.188388
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = 'ebbe2ad47fef'
+down_revision = 'bf4bf948f860'
+
+from alembic import op
+
+
+def upgrade():
+    # taggings must be free from duplicates and must not have a primary key
+    op.create_primary_key('taggings_pkey', 'taggings', ['song', 'tag'])
+
+
+def downgrade():
+    op.drop_constraint('PRIMARY', 'taggings_pkey', type_='primary')

@@ 6,7 6,7 @@ from ..database import Base
 class Tag(Base):
     __tablename__ = "tags"
     id = sa.Column(sa.Integer, primary_key=True)
-    name = sa.Column(sa.Text, nullable=False, unique=True)
+    name = sa.Column(sa.Text, nullable=False, unique=True, index=True)
     songs = sa.orm.relationship("Song",
             secondary="taggings",
             collection_class=set,

@@ 3,6 3,6 @@ import sqlalchemy as sa
 from stewdio.database import Base
 
 taggings = sa.Table("taggings", Base.metadata,
-    sa.Column("song", sa.Integer, sa.ForeignKey("songs.id"), nullable=False, index=True),
-    sa.Column("tag", sa.Integer, sa.ForeignKey("tags.id"), nullable=False, index=True)
+    sa.Column("song", sa.Integer, sa.ForeignKey("songs.id"), nullable=False, index=True, primary_key=True),
+    sa.Column("tag", sa.Integer, sa.ForeignKey("tags.id"), nullable=False, index=True, primary_key=True)
 )