Mask email IDs in MSSQL

Masking email IDs in MSSQL can be done using string manipulation functions. Here's an example of a function to mask email IDs:

CREATE FUNCTION dbo.MaskEmail (@email VARCHAR(255))

RETURNS VARCHAR(255)

AS

BEGIN

    DECLARE @maskedEmail VARCHAR(255)

    DECLARE @atIndex INT

    SET @atIndex = CHARINDEX('@', @email)

    IF @atIndex > 0

        SET @maskedEmail = LEFT(@email, 1) + REPLICATE('X', @atIndex - 2) + RIGHT(@email, LEN(@email) - @atIndex + 1)

    ELSE

        SET @maskedEmail = 'Invalid Email Address'

    RETURN @maskedEmail

END;

Usage:

SELECT dbo.MaskEmail('example@email.com') AS MaskedEmail;

This will output eXXXXXXX@email.com.

Here are few FAQs:-

1. Why should email IDs be masked in a database?

   - Email IDs are often used as identifiers and can contain sensitive information about individuals. Masking them helps protect user privacy and reduces the risk of unauthorized access to personal data.

2. Can the original email ID be retrieved from the masked version?

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

3. Does masking email IDs affect their usability?

   - Masking email IDs may affect their readability, but it doesn't necessarily impact their usability for operations that don't require the full email address. For example, masking can still preserve the domain part of the email, allowing for identification and categorization.

4. Are there any legal requirements for masking email IDs?

   - 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 email IDs.

5. Can I customize the masking format for email IDs?

   - Yes, the provided function can be customized to accommodate different masking preferences or variations in email ID structures. You can modify the function logic accordingly to meet your needs, ensuring that sensitive information is adequately protected while maintaining usability.