I'm looking to implement a transactional batch, whereby either all of the records are updated or none of the records are updated.  Please confirm or correct the following:

A) Sesame does not have the ability to wrap multiple updates into a single transaction.  Thus, when using XResultSetValue to perform an update, each call is its own discrete "transaction".
B) A record in Sesame is locked if and only if it is the current record in a result set, whether that result set is being managed by a form or managed programatically via the XResultSet commands.

Assuming those two statements are true, I'll go ahead and implement my plan for a transactional batch.  If my assumptions are incorrect though, I'll have to revise my plan, so I'd rather know up front if I'm on target or not.

(BTW, does this mean that it is possible for a form update to only partially complete?  i.e. If a user updates multiple layout elements in a form, and the server crashes in the middle of a save, can this result in a partial update?)

For the curious, my plan for a transactional batch is the following (a quasi-two-phase-commit):

1) Update each record in the batch with a unique transaction key.
2) Once all processing is complete, record the transaction as being ready to commit using a record in a separate database which only holds transaction keys.
3) Complete the update by re-running through the result set and doing the true update.
4) Flagging the transaction key as being committed in my separate "transaction" database.
5) On startup, search the "transaction" database for partially committed transactions.  If found, complete the transaction.