Allow relaying just for ip that match domain?

hello, i need to make postfix to allow relaying just for ip that match
and ip address and domain, i managed to do
part with relaying by using mynetworks like this:

mynetworks = proxy:mysql:/etc/postfix/mysql_mynetworks.cf

and content of mysql_mynetworks.cf:

user = user
password = pass
dbname = database
table = allowed_hosts
select_field = IP
where_field = IP
hosts = 127.0.0.1
additional_conditions = and active='1'


but i need to allow relaying for domain example.com only if domain
example.com matches ip 10.0.0.1.

this is how currently table allowed_hosts look like:

active enum('1','0')
IP varchar(15)
Client varchar(128)
Comments text


fields Client and Comments are for me to know which client is and
notes for that client... but i need to add domain
check...

Any help is preciated...


Thanks...