I need to obtain the following thing:

I need to generate I number consecutive, without there are jumps among them, so that it
admits the handling of multiple clients, each one acquiring following the next consecutive respecting the order.
The great problem is that the transaction is slow (take approx 10-30 sec) and can have but of 8 clients
soliciing a consecutive one To the time...

This is:

Client 1 begins the transaction, asks for the next consecutive, he acquires the consecutive 1
client 2 begins the transaction and client 1 has not finished. The client 2 MUST WAIT until client 1 confirm or cancels the transaction,
and to acquire consecutive the consecutive number 2

I Try placing the IsolationLevel=adXactIsolated property but he does not work...

The only idea i have is to use a flag, but exists one better solution?

Thanks

(Ok, this problem rely in a not so good bd structure, but i don't can change that now)