Implement a dynamic data masking solution for sensitive data access
Instruction: For SQL Server, explain how you would use dynamic data masking to reduce accidental disclosure, configure access separately, and verify the limitations for users who can run arbitrary queries.
Updated
Official Answer
SQL Server dynamic data masking changes query-result display for principals without unmasking privileges. It does not encrypt or replace stored data. Users with broad query access may infer hidden values through predicates and repeated queries.
For the support workflow, identify the minimum fields and rows needed, restrict permissions and the query surface, then add suitable masks to reduce accidental exposure. Limit unmasking and mask-administration privileges separately. Administrative privileges can bypass masks.
Test three principals: a masked reader, an approved unmasked reader and a user denied read access. Check application output, exports, updates and alternate access paths. Masking should not grant the denied user access; it also does not remove write permission.
Do not promise secrecy while granting unrestricted queries against sensitive data. A restricted view or service and appropriate row/column permissions may be necessary. Audit access and test inference risks.
Assessment
A strong answer distinguishes masking, authorization and encryption and tests privilege differences. Claiming that a masked column makes all SQL access safe is a substantive error.