Distributed Transactions: XA

Hi there,

I just started reading about distributed transactions. The first thing I learned is that there is a standard (XA) from the Open Group for Distributed Transaction Processsing (DTP).

Then I learned, that many vendors support Distributed Transactions among servers of the same vendor. (SQLBase, Interbase...) This seems to be very confortable and transparent to the user.

Finally I got the impression, that this products do implement DT's in their own propietary way (not XA) and they do not offer an API conforming to XA.

Finally I read about Transaction Servers (TS) wich implement the XA way of doing things.

So now the questions:

1. Why ist the XA modell so complex?
2. Will only XA compilant Databases work with a TS?
3. Why won`t poor mans "2 Phase Commit" work?

//prepare commit operation

	for each (database in transaction) do
		begin
		if not (prepare commit) do
			begin
			rollback everything
			exit
			end
		end
	


	//commit 


	for each (active database server) do
		begin
		commit
		end

Thanks.

Marco Received on Fri Jan 28 2000 - 00:00:00 CET