>But if I'm updating the data, the session failed.
>Is it the correct action of TAF? Does TAF support an update >transation's failover?

In version 805 - no, TAF support only cursors (you can continue fetch). I believe in 815 and 816 it is also no.

The reason I think so: it is really expensive to replicate memory(i.e all uncommited session status) from one node(or server) to another.