Treats the columns of the input table as columns from other tables.For each column, filters out any values that are not present in its respective output column.
The expression that generates the set of columns to be remapped.
The name of the output column.
A table that contains all the rows in column(s) that are also in Expression.
TREATAS assigns the data lineage of the columns returned by the expression using the columns pass in the following arguments. The result can be assigned to a variable, because TREATAS is not a filter modifier. The first argument must be a table expression.
The TREATAS function works in Excel 2016 since version 1809. However, the function is not reported by IntelliSense and it might be not supported in Excel by Microsoft, yet.
Learn more about TREATAS in the following articles:
Propagating filters using TREATAS in DAX
This article describes how to create a virtual relationship in DAX using the TREATAS function, which is more efficient than approaches based on INTERSECT or FILTER. » Read more
Understanding the data lineage in DAX
Data lineage is a DAX feature so well-implemented that most developers use it without knowing about its existence. This article describes the data lineage and how it can help producing better DAX code. » Read more
Physical and Virtual Relationships in DAX
DAX calculations can leverage relationships present in the data model, but you can obtain the same result without physical relationships, applying equivalent filters using specific DAX patterns. This article show a more efficient technique to apply virtual relationships in DAX expressions. » Read more
Other related functions are:
Contributors: Alberto Ferrari, Marco Russo, Ed Hansberry
MSDN documentation: https://msdn.microsoft.com/en-us/query-bi/dax/treatas-function