BigData / Tableau Interview Questions
What is the difference between FIXED and INCLUDE LOD expressions?
Both add dimensions to control the level of detail, but they respond differently to whatever else you place on the view afterward.
| FIXED | INCLUDE |
| Ignores the view's own dimensions entirely; computes only at the fields listed. | Adds its listed fields on top of whatever the view already has. |
| Result stays constant even if you add more dimensions to the view. | Result can change if the view's own dimensions change, since they're additive. |
| Good for a true, fixed customer/order-level total regardless of context. | Good for a calculation that always needs finer detail than the view, whatever that view happens to be. |
{ FIXED [Region] : SUM([Sales]) } -- always Region-level, no matter the view { INCLUDE [Order ID] : SUM([Sales]) } -- view's dimensions + Order ID
A useful mental model: FIXED defines an absolute level of detail independent of the view, while INCLUDE defines a relative level of detail that's always at least as fine as whatever the view currently shows.
Does a FIXED LOD's result change if you add more dimensions to the view?
How does INCLUDE relate its listed fields to the view's existing dimensions?
More Related questions...
