DAX running total optimization : Using date column from dimension vs date from fact

tvaishnav Well, the best practice is whatever works in your particular situation. 😉  Generally speaking through, what you described is the conventionally accepted wisdom. However, it's not foolproof as you saw when using the date from the productivity table was running faster.

Running totals by day across 33M records is likely going to be problematic through however you try to slice it. Basically, for each date, you have to put all 33M records into memory, then filter that down but in some cases you are still dealing with tens of millions of rows over and over again for certain dates. You might try filtering your visual so that it only returns a set number of days. Also, you might try calculating this in Power Query or as a calculated column so that it runs as part of refresh instead of every time the visual is loaded.