Boundaries of Transactions
This is a summary of the decisions taken and conclusions made in the previous sections of this chapter:
Transactions are assumed to be
operation level consistent
. It is the programmers' responsibility to write them that way.
guaranteed to be isolated, so additional locking may be required to guarantee
system level consistency
after having been committed on the server.
Transactions that are
seem committed to a client.
Transactions cannot be nested.
A new algorithm for optimistic concurrency control was sketched.
Explicit begins and ends, and new transaction operations are needed.