Filter ComboBox with a specific data table/source column

[AndyH_JSY]

Hello!

I have a PowerApp that uses an Excel spreadsheet (called BackendDatabase) in OneDrive as the data source for a Power Apps data table (called DataTable1). 

This table contains columns and rows with info such as Customer Names, Device Names, Location Names, etc.

I have 2 ComboBoxes:

 - ComboBox1 (CustomerNameInput) the 'Items' field is set to BackendDatabase.DeviceName. When this is selected it filters the DataTable by the selected customer name, so details for only those customers show up. 

- ComboBox2 (DeviceNameInput) the 'Items' field of this is BackendDatabase, and the reasons for this is I needed to make a Collection of the 'Device Locations' column from the 'Backend Database' but only display the 'Device Name' field. What I have done is set the Display Field property to 'Device Name'.

(Capture.png shows the screen)

So what I am trying to do is select a customer name in ComboBox 1, and then filter either the DataTable or Backend Database, to only show the 'Device Names' field for that customer. 

Any suggestions welcomed and happy to provide more info!

Thanks in advanced

[Drrickryp]

Hi @AndyH_JSY 

If you have one table with devices and customers then you are already starting with a flawed design for your app.  It sounds like you have a One to Many relationship between customers and devices, ie. one customer can have many devices.  If this is the case, you should have two tables, One for customers and One for devices.     Please check out my post regarding database principles and PowerApps starting with the overview. https://powerusers.microsoft.com/t5/News-Announcements/Database-Design-Fundamentals-and-PowerApps-An... .  It should help you better design your app.