Updating the permissions for the db user have any effect on existing connections?

Question

I am thinking to add few more permissions to existing database user in a database in MySql db. This is in production and serving a large user group. Will updating the permissions for the db user have any effect on existing connections?

Answer 1

Permissions are established at login time.

MySQL 8.0 and MariaDB 10.0 have added "Roles" for simplifying the establishment of permissions for large numbers of users.