How to Enable Data Masking for Sensitive Columns in SQL

Enabling Data Masking for Sensitive Columns

Write a SQL query to enable dynamic data masking on a sensitive column.

Solution:

-- Enable dynamic data masking on the SSN column.
ALTER TABLE Employees
ALTER COLUMN SSN ADD MASKED WITH (FUNCTION = 'partial(0,"XXX-XX-",4)');

Explanation:

• Purpose of the Query :
• The goal is to demonstrate how to mask sensitive data to protect privacy.
• Key Components :
• ALTER COLUMN: Modifies the column to include data masking.
• MASKED WITH: Applies a masking function to obscure sensitive data.
• partial(0,"XXX-XX-",4): Masks all but the last four digits of the SSN.
• Why Use Data Masking? :
• Data masking protects sensitive information while allowing limited access for testing or reporting.
• It simplifies compliance with privacy regulations like GDPR.
• Real-World Application :
• In healthcare systems, data masking protects patient identifiers.

Additional Notes:

• Dynamic data masking is supported in SQL Server and Azure SQL Database.
• Test masking rules to ensure they meet security requirements.
• Important Considerations:
• Ensure that masked data remains usable for its intended purpose.

For more Practice: Solve these Related Problems:

• Write a SQL query to enable dynamic data masking on the Email column in the Users table, showing only the domain name.
• Write a SQL query to mask all but the last four digits of the CreditCardNumber column in the Payments table.
• Write a SQL query to apply a default masking function to the PhoneNumber column in the Customers table.
• Write a SQL query to test and validate the effectiveness of a data masking rule on the SSN column.

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