Re: Q about overlapping transactions...

Please ignore that.
I would like to ask instead about the case of two data items that need to be altered in tandem - access to either of them before both are updated is an inconsistency. Serializability theory discusses various ways of scheduling concurrent transactions and in the case of incremental release of locks I am wondering how the dependency between the above mentioned data items is preserved if another transaction comes along and tries to read them. How is this transaction (T2) prevented from reading one item updated by T1 before T1 updates the other? In other words, how can T1 be forced to simultaneously release the two data item write locks in an incremental lock release system?

Thanks,
Chris Quinn Received on Tue Aug 28 2001 - 12:21:56 CEST