Selective access based on property
I have a list of customers belonging to a region . Every customer is linked to a unique account manager. I have a SYS- Customers module, with the customer list as a dimension and the account manager as a list-formatted line item and the region as a list-formatted line item. The lists of account managers and regions are flat list, they are not part of the customer hierarchy since I need to aggregate customers into other parent lists.
I want to set up selective access on the region,so that each account manager only sees the regions in which his customers are located.
How can I make the link between account manager and region?