expression is testing fine, but value is not showing up in the app

[SANDRALAICHE]

I know this is going to be something simple, but I have been stumped for hours, I have tried so many different select formulas and have now just created a virtual column to first make a list of the values from the other table instead, I am trying to do a simple Balance Due Column that subtracts the list of payment amounts from the Invoice Amount Column, please help:

I have checked that all of my data types that I am creating the list from are all Price.

Thanks

[Marc_Dillon · Accepted solution]

[Balance Due] should probably be a virtual column, not a real column. Are you aware of the difference in when they evaluate?

[invoice Amount] - SUM( [Related Payments][Payment amount] )

https://help.appsheet.com/en/articles/2357307-sum

https://help.appsheet.com/en/articles/4575708-list-dereference

[SANDRALAICHE]

No, I am very new at this, and am finally going to try to just take a course and start from the beginning and learn some of those things that I have been missing, I appreciate the response and I think I can clean up quite a few of my select formulas that are slowing my app down now that I understand the list dereferences.  Thank you so much!!

PS an explanation regarding the difference in the evaluation would be great!!

[Marc_Dillon]

Virtual evaluates on every sync, real evaluates only when the record is edited.