The SAP Transaction Model: Know Your Applications
SAP's transaction model uses databases as simple transactional stores that administrative staffs know how to manage. We have our own Application Database Interface Layer outside the database that handles caching, locking, collection of updates and multi-tenancy. Transaction commit on the actual database is handled using the recently rediscovered two-stage approach. This approach reduces load on the database, since transactions that update the database will commit with a single message into the database, and because of the two-stage approach, almost all transactions commit succeed. Presented at conference SIGMOD2008 by S.Finkelstein, R.Brendle, D.Jacobs, M.Hirsch and U.Marquard, SAP Labs.