Level of Detail - at database level and LOD in Tableau
Tabel Calculations explanation
http://www.vizwiz.com/2017/02/table-calcs.html
When changing Compute Using then notice that Specific Dimensions ticks also change, you can learn from it
How to understand what to tick and what to not
untick those that you want your calculation to start over
Cohort one simple explanation - people that did something at the same date
Right click drag
Question number comes from one Data Source and Description from another. Create Primary Group creates alias values, no performance issue later on. Works only for cases where values dont change or for proof on concept
Create your own areas
Use map on map in tooltip - it seems like zoom