Protecting Sensitive Data with Always Encrypted in SQL

Enabling Always Encrypted for Sensitive Data

Write a SQL query to enable always Encrypted for a sensitive column.

Solution:

-- Enable Always Encrypted on the CreditCardNumber column.
ALTER TABLE Customers
ALTER COLUMN CreditCardNumber NVARCHAR(25) COLLATE Latin1_General_BIN2
ENCRYPTED WITH (
    ENCRYPTION_TYPE = DETERMINISTIC,
    ALGORITHM = 'AEAD_AES_256_CBC_HMAC_SHA_256',
    COLUMN_ENCRYPTION_KEY = CEK_Auto1
);

Explanation:

• Purpose of the Query :
• The goal is to demonstrate how to use Always Encrypted to protect sensitive data.
• Key Components :
• ALTER COLUMN: Modifies the column to enable encryption.
• ENCRYPTED WITH: Specifies the encryption type, algorithm, and key.
• DETERMINISTIC: Ensures consistent encryption for querying.
• Why Use Always Encrypted? :
• Always Encrypted protects sensitive data from unauthorized access, even by database administrators.
• It ensures compliance with data protection regulations.
• Real-World Application :
• In e-commerce systems, Always Encrypted secures payment information.

Additional Notes:

• Always Encrypted is supported in SQL Server and Azure SQL Database.
• Manage encryption keys securely to prevent data loss.
• Important Considerations:
• Test encrypted queries to ensure compatibility.

For more Practice: Solve these Related Problems:

• Write a SQL query to enable Always Encrypted for the "SSN" column in the "Employees" table.
• Write a SQL query to encrypt the "BankAccountNumber" column using deterministic encryption for querying.
• Write a SQL query to enable Always Encrypted for all sensitive columns in the "Customers" table.
• Write a SQL query to test encrypted queries on a column protected by Always Encrypted.

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