Manage transaction

[amanteaux]

Transaction are currently not handled: no data are cached during a transaction and no cache are cleaned during a transaction.

A transaction system should be provided which will replay all requests incidence on the cache once the transaction has been committed. For example if a transaction contains 2 queries select a from b and delete from c, once the transaction is committed, the query result select a from b should be cached and any query referencing the c table should be cleaned.

What could be done to implements this behavior is to have a custom connexion that would contain a scenario variable. This scenario would then be filled by each statement in the transaction. At the commit of the transaction, the scenario will be played.

[amanteaux]

Actually, the select queries should not produce a cache entry since the database may change before the transaction is finished. For example:

1. transaction is started
2. transaction: select a from b
3. outside transaction delete from b
4. transaction is finished

=> the b table cache should be empty