Add an index to the image storage uuid to improve performance.

data/database.py

@@ -257,7 +257,7 @@ class EmailConfirmation(BaseModel):
 
 
 class ImageStorage(BaseModel):
-  uuid = CharField(default=uuid_generator)
+  uuid = CharField(default=uuid_generator, index=True)
   checksum = CharField(null=True)
   created = DateTimeField(null=True)
   comment = TextField(null=True)

data/migrations/versions/b1d41e2071b_add_an_index_to_the_uuid_in_the_image_.py

@@ -0,0 +1,22 @@
+"""Add an index to the uuid in the image storage table.
+
+Revision ID: b1d41e2071b
+Revises: 9a1087b007d
+Create Date: 2014-10-06 18:42:10.021235
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = 'b1d41e2071b'
+down_revision = '9a1087b007d'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade(tables):
+    op.create_index('imagestorage_uuid', 'imagestorage', ['uuid'], unique=True)
+
+
+def downgrade(tables):
+    op.drop_index('imagestorage_uuid', table_name='imagestorage')