Charles, just to make sure I'm following you here, you want to select a company from a dropdown list of 300 companies and once you do that you want another dropdown to filter to ONLY the customers/stores within that selected company? If yes, I assume you have a dimension for company and another for customer/store? If no, can you please clarify. Thanks.
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kenneth, it s organized as follows:
Parent Company, Customer Name, Customer Level(Parent Company or Store Level)
so, if it was a parent company, the customer name would also be the same as the parent company and the customer level would be parent company if that makes sense