Hello @oviland!!
That’s a great question, and there are several ways to approach it.
1. Tables API
The Tables API (https://support.tulip.co/en/articles/3983173-how-to-use-the-table-api 
) can be used to get all records in a Table. You can then use the returned array to populate the options in a single select that can be populated from a Text Array (see Options & Variable fields on the Widget tab):
2. Create an ID Table
Create another Table with the unique ID’s of the Orders, and use that to filter the Order Details Table. Something along the lines of:
Display both the Order Details and Order ID tables in an app, link a Record Placeholder to the Order ID Table & add a trigger to store the selection in a Variable:
Filter the Details Table with the Order ID (on the Order ID field):
This is the result of this app:
Do either of these approaches work for what you’re trying to build??
Would you like to join office Hours this Thursday at 11AM EST (https://community.tulip.co/t/tulip-office-hours-10-15/791)?? It would be a great topic to cover. Let me know if this is of interest to you and I can add you to the invite!!
Gio