rails/activerecord-session_store — pull request #13 by stevehodgkiss (2013-07-04 04:41:03+00:00)
Title: session_id should have a unique index

The session migration generator creates the sessions table without a unique index on session_id, whereas `ActiveRecord::SessionStore::Session.create_table!` creates it with a unique index.

This change makes them consistent in having a unique index on session_id.