Power BI | Advanced data sources exercise | Connecting to folder data sources

This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.

Software ==> Power BI  (111 exercises)
Version ==> Latest update
Topic ==> Advanced data sources  (4 exercises)
Level ==> Relatively easy
Subject ==> Power BI training
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Movies come in a variety of different genres - these are currently stored in separate workbooks. Using the Folder data source option combine all the genres into a single data model table:

The files to combine

The files in the above folder that you want to combine (but see hint below).


Note that one of the files above has an .xxx extension (and so won't import properly), so after choosing to combine your files be sure to tick the Skip files with errors box.

This will give you 321 films, in 3 different genres.  Return to Power BI proper and create a Table visual to compare their lengths:

Table Visual Power BI

Your table should show the average run time for each genre.


It would appear that the shorter the movie, the better it is.  Let's test this hypothesis by adding some truly terrible movies into our data model!  Firstly, rename the file Awful Films.xxx in the above folder to Awful Films.xlsx, then load it into your data model:

Two loaded tables

You now have two tables (which we've renamed), which you should combine as explained below.


Use the Append option in query editor to append one of these queries onto the other.  You should now have 326 films in your combined table, not 321:

The combined films

The combined table of films, beginning with the 5 awful ones (at least according to Wise Owl).

Create a column chart based upon the combined table to test your hypothesis:


It seems as if the hypothesis doesn't stand up in the face of data!

Optionally save this as Are shorter movies better, then close it down.

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.
This page has 1 thread Add post
02 Dec 18 at 02:11

It seems like the download zip is missing some files. It only has Awful Films spreadsheet. Is there another link to download Action, Comedy, and Romance Films spreadsheets?

Thank you,

03 Dec 18 at 18:28

You were correct!  I've rewritten the exercise, and it should all now work - thanks.

17 Dec 18 at 14:55

Hi Andy B,

the files are still missing. Only "Awful Films" is there with correct extension .xlsx. 

Andy B  
17 Dec 18 at 18:34

OK, I really HAVE updated them now - just checked.  Missed out one stage of the process before.