Rollup fields/columns can be used to aggregate your data, using functions of SUM, COUNT, MIN, MAX and AVG. These are built in Dataverse, which means you can use them across Power Apps and Dynamics 365.
In this hands-on tutorial, I’ll show you how to build a new rollup field/column from scratch (using Accounts and Opportunities in the Dynamics 365 Sales app), how to add it to a form, and then how to test/recalculate the sum.
You might also enjoy this video about calculated fields: https://youtu.be/_Lin22-607U
00:00 – Overviewing the completed rollup field/column in the Dynamics 365 Sales app
01:39 – Working with tables and columns in Dataverse (at make.powerapps.com)
02:32 – Creating a new rollup field/column
05:50 – Adding a new column/field to a form
07:00 – Testing and recalculating the rollup field/column
If you want to set up a free 30-day trial of Power Apps, check out another one of my videos: https://youtu.be/9attR2JnQnU.