Encryption-Based Multilevel Model for DBMS - Multilevel Security for Relational Databases - page 94

Get user class L(user)

Set i = 1

i = i + 1

A i ∈ R [A i ]*

No Ye s

A i = null

C i = L(user)

K = K Ci

A i = E (K, a i )

TC = L (user)

Insert the row

End

Figure 5.1 Flow chart for insertion operation in the encryption-based multilevel database model.
(A. Rask, D. Rubin, and B. Neumann. 2005. Implementing row- and cell-level security in classi-
fied databases using SQL server. Available at http://technet.microsoft.com/en-us/library/cc966395.
aspx; accessed April 2011.)

Figure 5.2 illustrates the flow chart for the delete operation in the
encryption-based multilevel database model.

5.3.3 he SELECT Statement

The SELECT statement executed by a user with security class level L
has the following general form:

SELECT [A 1 ,A 2 ,...,A n ] FROM R
WHERE P