Power Fx function

As — Power Fx function reference

Alias a record scope.

Syntax

powerfx

Source As AliasName

powerfx

ForAll(Orders As O, O.Amount * 1.1)

→ Avoids name clashes

powerfx

ForAll(Orders As Ord, LookUp(Customers As Cust, Cust.ID = Ord.CustomerID).Name)

powerfx

Filter(Products As P, CountRows(Filter(OrderLines As L, L.ProductID = P.ID)) > 0)

Use As when nesting galleries or ForAll so inner and outer rows do not collide.
Without As, a nested ForAll/Filter's inner ThisRecord/ThisItem shadows the outer one, making the outer row unreachable by name — As is the required fix whenever both rows are genuinely needed.
The alias only applies within that specific function call's scope; it does not rename the data source globally or affect other formulas elsewhere in the app.

From Records & scope references