When we’re talking about iterating function ,
Question : Is that evaluated per row and kept in memory for only rows related to each cell in filter context?
When we try to see Total Sales product wise but for channel = “Export”, we see below figure using SUMX
Product 7 -->3973662.80
So does mean filter propagation results us first the set of rows related to product = product 7 in sales table & than for each row conditions are applied to filter channel & adding each row to memory that satisfy this filter.
And once rows for Product 7 are collected into memory sumx perform aggregation on top of same.