I'd say it's brutal to ask users to scroll down to select pages and pages of Customers (no offence!). I'd suggest one of the two:
1. Use the feature "Searchable" for your Expressions (in the Presentation tab). This way, users should be able to type ">500" and get the list of the Customers. They won't get selected though.
2. Offer an input box with a variable and a button "Select". The user enters the value "500" and the button facilitates an Action that selects Customers with more than 500 units. To make it more flexible, you can allow selecting what field to select in (Customer, Item, Salesperson) and what measure to calculate (Units, Dollars, profit margin). This way, you let users define their search criteria and get dozens of Customers selected at once.
Hi Oleg, many thanks for your answer.
Many times, users don't know what threshold to use, they just check customers until they see "that something" that makes them decide, then click and drag to the top (it's under 1 second time, and usually better than typing on the keyboard).
Also, we already had something similar to your option "2", but it is in a different form and they use this kind of selection based on a specific table. We could not replicate this kind of selector on all the tabs and tables.
BUT, your first option (searchable column) did the trick - in fact, it DOES select customers in our case (probably because the expression is a $(function) that is quite complex).
Anyway, making most expressions "searchable" will be a development rule from now on.