Cross Joins in Power Query: Measuring Student Progress
In this video we’re measuring student progress against program requirement. A full outer join is used as a final step. However, the cross join is needed so that we can identify where students haven’t done ANY work in a category. The full outer join won’t pick up data that doesn’t exist.
What is a Cross Join? It’s a way of merging data when you need everything on List 1 to be matched with everything on List 2.
A cross join isn’t one of the 6 joins packaged in Get & Transform (Power Query) and isn’t used much. However, the cross join does have a purpose.
This video shows how easy it is to make a cross join but more importantly:
– A practical example of when to use a cross join.
– Why a cross join was used instead of other joins or Get and Transform (Power Query) features.
In this situation, we’re measuring student progress against program requirement. A full outer join is used as a final step. However, the cross join is needed so that we can identify where students haven’t done ANY work in a category. The full outer join won’t pick up data that doesn’t exist.
Website: https://ozdusoleil.com
My book: Guerrilla Data Analysis 2nd Edition
http://www.amazon.com/Guerrilla-Analysis-Using-Microsoft-Excel/dp/1615470336
My old blog: http://datascopic.net/blog-2-2