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Handling Personal Data in Pipelines

Techniques for protecting personal information as it moves through data pipelines: masking, tokenisation and access control.

Editorial team 1 min read

Pipelines often carry personal data from source systems into warehouses, analytics and AI. Protecting it is a core engineering responsibility.

Classify

Tag columns and datasets containing personal or sensitive data, ideally automatically, and record them in catalogues.

Minimise

Only copy personal fields that downstream uses need.

Protect

  • Masking: hide values from users who don't need them.
  • Tokenisation and pseudonymisation: replace identifiers with tokens, keeping joins possible.
  • Encryption in transit and at rest.
  • Row- and column-level access policies in warehouses.

Non-Production Environments

Don't copy real personal data into development and testing environments; use masked or synthetic data.

Deletion Requests

Design pipelines so records can be deleted across all copies when people exercise their rights.

Logging

Avoid personal data in pipeline logs and error messages.

Audit

Track who accesses sensitive data and review regularly.

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