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7 – One-Way EncryptionEXECUTE AS USER = 'KELLEYWB';GOExec dbo.Search_Borrower_Identification '0143';GOREVERT;GO-- execute as a user who is a member of Sensitive_low roleEXECUTE AS USER = 'JONESBF';GOExec dbo.Search_Borrower_Identification '0143';GOREVERT;GOListing 7-15: Verifying permissions.The result of this verification will reflect that rows were returned for thequeries for the Sensitive_high and Sensitive_medium members; butsince permissions did not exist for the Sensitive_low members the actualrows will not be returned. Instead the following will appear:(1 row(s) affected)(1 row(s) affected)Msg 229, Level 14, State 5, Line 1The EXECUTE permission was denied on the object'Search_Borrower_Identification', database'HomeLending', schema 'dbo'.To view the actual rows returned, execute each batch in this script individually.SummaryThrough this demonstration we have successfully implemented one-wayencryption for the Borrower_Identification table of ourHomeLending database. This addresses only the plain text in a single columnof a single table. Within the database there are many more columns that may begood candidates for one-way encryption.Through our exploration of the various attacks that can be waged against datathat is protected with one-way encryption, and our better understanding of thepotential for hash collisions, we have a better understanding of when the optionto apply one-way encryption is valid and when it is not.169