Complicated dependent dropdown from two ref tables

[richard_s]

Hi folks, I’m trying to create a dependent dropdown with customers and its devices. I have a table called RepairList and in this table I am referencing Customer Name from table Customer and Device_ID from table called Devices. I want to be able to select any customer from the table Customer, and then select Device ID and, I want to see only the devices which belong to the customer.

I tried doing this with dependent dropdowns valid_if which works fine in case, I want to see only the customers that own devices. However, what I am trying to do here is that I want to see all the customers even though they may not have any devices, in case they don’t own any, I can easily a add new device which would belong to them. I have tried all the things related to SELECT, dependent dropdowns, FILTER, valid_if that I have found on the forum. However, nothing seems to work for me, and I cannot figure out how to use them in this case. Could anyone this of precise formula that would solve my issue please? For better understanding of my data, I have attached images from my excel below. Thanks

IMAGES FROM MY EXCEL:

[Steve · Accepted solution]

RepairList table Customer column Valid If expression:

FILTER("Customer", TRUE)

RepairList table Device column Valid If expression:

FILTER("Device", ([Customer] = [_THISROW].[Customer]))

[richard_s]

Thank you very much! It works marvelously.