Power BI has a great query setup to preprocess data before it feeds graphs. It can take many somewhat repetitive columns and reduce the number of columns by pivoting just those columns to one. Let’s say a list is columned such as below.
Digits are a representation of a part. In column names at the right of the dash, if M = Module, L = Lesson, A = Asset, then all we need are these 3 to be columns and a 4th Group column to be the identifier from the left side of the dash in headers.
In the Query Editor, columns in the first table are pivoted up on its side to form two columns with names and digits. The column of names is split in two, divided by the – dash, leaving a column of M,L,As. Change this column data to be Module, Lesson, Asset, respectively. Transform this column back to 3 columns heading: Module, Lesson, Asset. Power BI can compensate for lists of any type or databases, including REST queries.