Identifies a subset of columns specified in the call to SUMMARIZE function that should be used to calculate subtotals.
The GroupBy_ColumnName parameter must be a qualified name of an existing column to be used to create summary groups based on the values found in it.
The ROLLUP function is used exclusively within SUMMARIZE.
The columns mentioned in the ROLLUP expression cannot be referenced as part of a GroupBy_columnName columns in SUMMARIZE.
Learn more about ROLLUP in the following articles:
Best Practices Using SUMMARIZE and ADDCOLUMNS
Everyone using DAX is probably used to SQL query language. Because of the similarities between the Tabular data modeling and the relational data modeling, there is the expectation that you can perform the same operations as those allowed in SQL. However, in its current implementation DAX does not permit all the operations that you can […] » Read more
All the secrets of SUMMARIZE
SUMMARIZE is a function that looks quite simple, but its functionality hides some secrets that might surprise even seasoned DAX coders. In this article, we analyze the behavior of SUMMARIZE, in order to completely describe its semantic. The final advice might surprise you: we will suggest to avoid the use of SUMMARIZE in your code, […] » Read more
Other related functions are:
Contributors: Alberto Ferrari, Marco Russo