James Henstridge wrote at 2008-1-25 09:48 +0900: >On 25/01/2008, Dieter Maurer <[EMAIL PROTECTED]> wrote: >> This description suggests that the TM provides the "main" transaction >> identifier and the resource manager could add the branch part. > >I guess the reason why the TM generally assigns the branch qualifiers >in XA systems is that it is in the best place to do so: it can simply >issue sequential numbers to each resource that joins the transaction. >An RM has no knowledge of what other branch qualifiers have been used >so would need to do something more comlpex.
It could identify itself -- and then there would be no need to know other branch qualifiers. >Now whether the TM or RM generates the branch qualifier, I'd expect >that the TM needs to know all the full transaction IDs if it is to >properly handle recovery. If the RM is generating the ID, then the TM >would now need some way to retrieve that ID. The "conn.xid" could provide the part identifying "conn". -- Dieter _______________________________________________ DB-SIG maillist - DB-SIG@python.org http://mail.python.org/mailman/listinfo/db-sig
