Question

A retail analytics team must run demographic reports on a dataset containing customer national ID numbers stored in a cloud data warehouse. Legal requires that raw national IDs never reside in the warehouse or be recoverable by analysts, yet the reports must still correlate records belonging to the same customer across multiple tables and preserve the original field length/format for the legacy reporting tool. Which data protection design best meets these requirements?

Accepted Answer

Apply deterministic format-preserving tokenization at ingestion, storing raw IDs only in an isolated token vault outside the warehouse

Answer

Encrypt the national ID column with AES-256 using envelope encryption and grant analysts decrypt permissions on the KMS key

Answer

Apply randomized (non-deterministic) tokenization to each occurrence of the national ID at load time

Answer

Hash the national IDs with SHA-256 and a per-table salt before loading them into the warehouse