one mysql database per domain with amavisd-new while having multiple domains

[Damian]

> How can I grant  admin at example.com to view only his own domain records and
> admin at client1.com to view only his own domain records?
>
> how can I grant permission? all tables have all hosted domain records.
>
> How can I reach my goal with mysql while having one database?

Amavis does not have an answer to these questions. PostgreSQL has
row-level security, MySQL I don't know.