Mask mobile numbers in DB2

Masking mobile numbers in DB2 can be achieved using string manipulation functions. Below is an example of how to implement this:

SELECT 

    CASE 

        WHEN LENGTH(mobile_number) = 10 THEN CONCAT('XXX-XXX-', RIGHT(mobile_number, 4))

        WHEN LENGTH(mobile_number) = 11 THEN CONCAT('XX-XXX-', RIGHT(mobile_number, 4))

        WHEN LENGTH(mobile_number) = 12 THEN CONCAT('X-XXX-', RIGHT(mobile_number, 4))

        WHEN LENGTH(mobile_number) = 13 THEN CONCAT('XXX-XXXX-', RIGHT(mobile_number, 2))

        WHEN LENGTH(mobile_number) = 14 THEN CONCAT('XX-XXXX-', RIGHT(mobile_number, 2))

        WHEN LENGTH(mobile_number) = 15 THEN CONCAT('X-XXXX-', RIGHT(mobile_number, 2))

        ELSE 'Invalid Mobile Number'

    END AS masked_mobile_number

FROM your_table;

This query masks mobile numbers based on their length.

Example:

Let's say the original mobile number is '1234567890':

SELECT 

    CASE 

        WHEN LENGTH('1234567890') = 10 THEN CONCAT('XXX-XXX-', RIGHT('1234567890', 4))

        WHEN LENGTH('1234567890') = 11 THEN CONCAT('XX-XXX-', RIGHT('1234567890', 4))

        WHEN LENGTH('1234567890') = 12 THEN CONCAT('X-XXX-', RIGHT('1234567890', 4))

        WHEN LENGTH('1234567890') = 13 THEN CONCAT('XXX-XXXX-', RIGHT('1234567890', 2))

        WHEN LENGTH('1234567890') = 14 THEN CONCAT('XX-XXXX-', RIGHT('1234567890', 2))

        WHEN LENGTH('1234567890') = 15 THEN CONCAT('X-XXXX-', RIGHT('1234567890', 2))

        ELSE 'Invalid Mobile Number'

    END AS masked_mobile_number;

The result would be XXX-XXX-7890.

Here are few FAQs:-

1. Why should mobile numbers be masked in a database?

   - Mobile numbers can contain sensitive information, and masking them helps protect user privacy and prevents unauthorized access.

2. Can the original mobile number be retrieved from the masked version?

   - Ideally, the masking process should be irreversible to maintain data security. Therefore, the original mobile number should not be easily retrievable from the masked version.

3. How can I ensure that masked mobile numbers remain usable for certain operations?

   - By retaining some part of the original mobile number, such as the last few digits, you can maintain the usability of the data for operations like identification or verification while still protecting sensitive information.

4. Are there any legal requirements for masking mobile numbers?

   - Depending on the jurisdiction and the nature of the data being handled, there may be legal requirements or industry standards mandating the protection of personally identifiable information (PII), which includes mobile numbers.

5. Can I customize the masking format for mobile numbers?

   - Yes, you can customize the masking format according to your requirements. The provided query can be modified to accommodate different masking formats or variations in mobile number structures.