In our recent Tableau 9.0 Feature Highlights and Overview post (here) we briefly mentioned the Level of Detail calculation features which will be available with the forthcoming Tableau 9.0 release. This week, we’ll take a look in a little more detail at some of the new expressions and the capabilities that these features will provide.

The basic idea behind the Level of Detail (‘LOD’) functionality is that you will have the ability to directly define the ‘level of detail’ or aggregation granularity level at which a particular calculation should be performed. In previous versions of Tableau, you were often constrained by the levels of the Dimensions in use within the View you were working, or you would be forced to created convoluted workarounds in order to utilize different levels within the same view. Most folks who have spent any time writing Tableau calculations are very familiar with the frustrations this could present, usually experienced while muttering expletives and repeatedly reading the error message: “Cannot mix aggregate and non-aggregate arguments with this function”. Well folks it’s time to let your calculations be free…

There are 3 new LOD expressions available to you which will provide the ability to create calculated fields which specify the level of detail for different scenarios. Here’s a quick summary of each:

FIXED: This expression sets the level of detail for your calculation by basing it on a particular dimension or dimensions independent of any other dimensions in the View.

INCLUDE: This expression allows you to specify other dimensions upon which to base the calculation in addition to the dimensions which are currently in use in the View.

EXCLUDE: This expression allow you to explicitly specify dimensions in use in the current View which should not be used in the calculation.

The syntax for Level of Detail expressions is as follows:

(This table is from Tableau’s online documentation. Click on the image below to see a full-sized view)

LOD syntax table

Summary

So – plenty of functionality to explore with these. We’ll be sure look at some examples and use cases for each of these in an upcoming post…stay tuned.

For the ambitious ones out there who’d like to do some more in depth reading, take a look at Tableau’s LOD overview here.