Validate email addresses in Mysql
You can use a pure SELECT to validate Email Addresses:
SELECT * FROM `users` WHERE `email` NOT REGEXP '^[^@]+@[^@]+\.[^@]{2,}$';And now for your question of tracking multiple tables, you can use comma seperated table names right?
SELECT * FROM `users`, `customers`, `clients` WHERE `email` NOT REGEXP '^[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,63}$';
For the proper email validation, you can use this regex as bellow:
SELECT *FROM `school`WHERE `email` NOT REGEXP '^[a-zA-Z0-9][a-zA-Z0-9._-]*[a-zA-Z0-9._-]@[a-zA-Z0-9][a-zA-Z0-9._-]*[a-zA-Z0-9]\\.[a-zA-Z]{2,63}$';
Simple SELECT statement is sufficient, for example:
SELECT * FROM user WHERE email NOT REGEXP '^[a-zA-Z0-9][+a-zA-Z0-9._-]*@[a-zA-Z0-9][a-zA-Z0-9._-]*[a-zA-Z0-9]*\\.[a-zA-Z]{2,4}$'This query handles the Gmail addresses with + sign and addresses where the host is a single letter.