Swift 3 Core Data - NSExpression forFunction: “sum:” throws error (“could not cast dictionary to Day”)

Question

I have days and tasks. A day has many tasks. Every task has an attribute called \"points\" and I want to sum all points of the tasks of the current day. I used the code below (f

Answer 1

This solves my problem:

let sumRequest: NSFetchRequest<NSFetchRequestResult> = Day.fetchRequest()

Instead of putting Dayas NSFetchRequestResult, I put NSFetchRequestResult itself there. Now it's working.

I believe as I set it to a different resultType it's not [Day]anymore that gets returned, so that's why I needed to change that to be more generic or something.