Thanks Bill for very interesting and very detailed lessons.

But functions like DISTINCT, BLANK, SUM are relatively easy and trivial. Everyone who have ever worked with Excel or SQL will quickly figure out how to use them, even it's not so difficult to figure out the differences between SUM and SUMX.

But the really difficult functions that I expect to learn them here in Stairways are ALL, ROLLUP, CALCULATE, CALCULATETABLE, ADDCOLUMNS, ALLEXCEPT, FILTER, and especially combinations of them, the proper order of nesting, and how to use them and convert from EVALUATE context in SSMS to calculated dimensions and measures in model design.

Thanks