Dimensions and measures
Why is it important to understand dimensions and measures?
Understanding dimensions and measures are not specific to LOD calculations but a fundamental aspect required to learn Tableau and data in general.
Dimensions are discrete columns of data, usually names but can also be numerical. In Tableau, they are represented by blue pills (picture).
Measures are continuous columns of data, usually numbers. In Tableau, measures are represented by a green pill (picture)
Granularity of data
The granularity of data is the amount of information within each row. The columns that make each row unique in your table can be used to determine your level of detail. This makes understanding your granularity of data critical in effectively using LOD calculations.
Level of detail
In Tableau, there is a view/window that contains your Level of Detail. The level of detail is determined by the dimensions contained in the row and column shelves.
The dimensions you use can have a hierarchical structure in the table
Aggregation/calculations in Tableau
What are aggregations in Tableau?
Aggregations are actions that Tableau performs to manipulate data. These actions can be but are not limited to summation, averages, and count.
How are aggregations/calculations performed in Tableau?