



 
Hi Colin, Suppose there are $m$ object roles and $n$ data roles in the system. There are $m$ way a user can be assigned an object role and $n$ ways a user can be assigned a data role and hence there are $m \timers n$ ways a user can be assigned an object role and a data role. The user can then be assigned any subset of the remaining $m  1 + n  1 = m + n  2$ roles. A set with $k$ elements has $2^k$ subsets so the number of ways a user can be assigned roles is \[m \times n \times 2^{m + n  2}.\] Penny  


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