Adding a md5 field into the database

I would like to add a md5 field into the database, it should be a copy of one existing field (eg. user_name), but hashed by md5.

I would like both fieds available (user_name and md5(user_name))

I’m usig CFDB – great plugin 🙂

https://ww.wp.xz.cn/plugins/contact-form-7-to-database-extension/