Chapter 59. Using Level of Detail Expressions to Create Benchmarks
One of the most powerful features that shipped with Tableau 9.0 was “Level of Detail” (LOD) functionality, which provides a syntax for explicitly assigning a different level of detail, or granularity, to a measure. This unlocks many valuable analysis opportunities, with just a few outlined in Tableau’s post, Top 15 LOD Expressions. I admit that I’ve probably leaned on this functionality too much since its release because it is such a handy way to get the exact results I am looking for.
This chapter shares one of my favorite uses for LOD expressions: the ability to create a constant measure that can be used as a benchmark. For example, sometimes you want to compare the performance of a KPI now versus a KPI last year. Another example is in split testing, where it is common to need to compare the performance of a variant recipe to the performance of a control recipe. In the past, table calculations were the easiest way to create these comparisons, but the simple LOD calculation I’m about to share makes the analysis slightly more foolproof because you do not need to worry about the scope or direction of a table calculation.
This chapter shares a specific use case for using LOD expressions, but is not a comprehensive training on what LOD expressions are and how they work. If you need more information, I encourage you to read the Tableau whitepaper, “Understanding Level of Detail (LOD) Expressions”.