Reapply oracle policy

Question

We are using Oracle VPD security feature, recently we encountered some problems, in several of our clients's database (8.1.7.3), we found that the oracle policy was not reapplied after we changed vpd user in a jdbc thin connection, following is the scenario:
We have a policy, looks like follows
ploicy
if user is A, return predicate A
if user is B, return predicate B
(1)
build up a thin connection
set user to A
create a prepared statement of sql "select * from order"
query
close connection
in (1), we did find that policy was applied and the predicate A
was returned.
(2)
build up a thin connection
set user to B
create a prepated statement of sql "select * from order"
query
close
in (2), we got wrong result, because policy was not applied, it
still use predicate A.
Any comments?
Thanks

Answer 1

the key is how you answer the question " how do you set your user ".
if you set user B by logging into db as user B, then the situation you descripted sounds like a bug, if I understand it right.
if you set by changing some variables inside the session, since the VPD engine does not know when you switch user, you could get old policy predicate if you reexecute the cursor or use PLSQL to rerun your static sql.
My suggestion is try out 9i that auto-reexecute the policy function.