Mask email IDs in Greenplum

Masking email IDs in Greenplum can be accomplished using string manipulation functions. Below is an example of how to implement this:

SELECT 

    CONCAT(SUBSTRING(email, 1, POSITION('@' IN email) - 1), 'XXXXX', SUBSTRING(email FROM POSITION('@' IN email))) AS masked_email

FROM your_table;

This query replaces characters before the '@' symbol with 'XXXXX', effectively masking the username part of the email address.

Example:

Let's say the original email ID is 'example@example.com':

SELECT 

    CONCAT(SUBSTRING('example@example.com', 1, POSITION('@' IN 'example@example.com') - 1), 

    'XXXXX', SUBSTRING('example@example.com' FROM POSITION('@' IN 'example@example.com'))) AS masked_email;

The result would be 'exampleXXXXX@example.com'.

Here are few FAQs:-

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

   - Email IDs are personal identifiers that, when exposed, can lead to privacy concerns or unauthorized access. Masking them helps protect user privacy and enhances data security.

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 easily retrievable from the masked version.

3. How can I ensure that masked email IDs remain usable for certain operations?

   - By retaining some part of the original email ID, such as the domain name, you can maintain the usability of the data for operations like communication or identification, while still protecting sensitive information.

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