Doubt about performance.

[JSO]

Doubt about performance.
Virtual fields are calculated when you start the application.
Does anyone know what the procedure is? These possibilities occur to me:
1- If they are calculated on the AppSheet server and the result is delivered to the device along with the rest of the data.
2-The device calculates them based on the data provided by AppSheet, without its collaboration.

I ask for the following:
If a virtual column has a heavy calculation, would it be more interesting to do it only when a record is changed and save it in the Table instead of doing it every time the application is loaded?

Can someone guide me?

[AleksiAlkio]

All virtual columns are calculated in server every time you sync, that's the basic. If you use gSheet and you have set the "Delta sync" option as ON, then it's only calculated with those tables that is updated or the table is related to that updated table.. but then your tables need to be in a separate workbook.