Apply VPD on this Logic ???

Question

I have to implement VPD on few tables. Table A,B has Depid and other columns which has to be hided. Every user is connected to a unique role. How to get the predicate using the role and Depid. Business logic is connected user should see only his/her data from A,B,.. through VPD.
Using sys_context I can get the logged in user and using a function how should I get the predicate. Any idea where should I start or other feasible methods?
Later this has to be extended to few more tables with out much customization and coding.
Thanks in advance for your time!

Answer 1

Acknowledging your gratitude.
What's your application architecture?Its DSS
The VPD function will then call that context and recover the user's id to generate the SQL predicate.How to get them from dictionary and bind them to get the depid as a predicate through a function?
That is explained in further detail here:?????
There you'll find examples of how to code your context packages/procedures.?????
It seems you want to use column masking for your VPD? Aka: hiding the values for the relevant column (depid) while still displaying the row with its other column values?No, column masking is not needed, just the basic column level VPD
If that's the case, there's a little sample on column masking VPDs here:
http://download.oracle.com/docs/cd/E11882_01/network.112/e10574/vpd.htm#i1014682
From the above link below example depno is hardcoded. Here I need to match the role to the depid(table structure above this thread) by sys context as a predicate. Any other methods welcome to try.
CREATE OR REPLACE FUNCTION hide_sal_comm (
v_schema IN VARCHAR2,
v_objname IN VARCHAR2)
RETURN VARCHAR2 AS
con VARCHAR2 (200);
BEGIN
con := 'deptno=30';
RETURN (con);
END hide_sal_comm;
Thanks!