Storing your users email addresses, dates of birth, or Social Security numbers in plain text poses a major risk in the event of a database breach. With robust application-side encryption, you can make the data unreadable by the database. However, this makes it impossible to run a query like `WHERE email = :value`. How can you secure your sensitive data without sacrificing essential business functionality?

We’ll explore how to implement client-side field-level encryption with Doctrine and a key management system. The algorithms to use, key management, and key rotation: learn how to turn your database into a vault without losing your ability to query it.