jackalope/jackalope-doctrine-dbal — pull request #75 by lsmith77 (2012-11-14 13:24:50+00:00)
Title: split the references into 2 tables to allow using defered FKs in the future

it might make sense to actually implement the deferred FK support.
Doctrine DBAL supports this for PostgreSQL, it should be possible to add this to SQLite as well.

note there is a typo in the PostgreSQL driver:
https://github.com/doctrine/dbal/blob/master/lib/Doctrine/DBAL/Platforms/PostgreSqlPlatform.php#L325

http://www.postgresql.org/docs/9.2/static/sql-set-constraints.html
http://www.sqlite.org/foreignkeys.html#fk_deferred