I created an app for a simple attendance regi...

expressions
(Mncedisi Trinity Dewa) #1

I created an app for a simple attendance register using barcodes. One of the tables for the lesson details has a field which is supposed to calculate the students recorded as present in the referenced table.

I used the expression:

COUNT(SELECT(Roaster[ScanCode],[LessonKey]=[_THISROW].[LessonID]))

The first time, the expression was working perfectly returning the number of students who would be recorded in the referenced table based on the scancode. Now it is always giving me a 0.

How do I resolve this?

I also verified and tested the expression. It is giving the right outcome but the result field continues to show a 0. Someone please help

(Suvrutt Gurjar) #2

Hello @Mncedisi_Trinity_Dew based on your description,is the said expression in the field of a parent table ? Is it a real column?

(Aleksi Alkio) #3

If you have a virtual REFROWS column, you could count it as COUNT([VirtualColumnName])

(Mncedisi Trinity Dewa) #4

Hello, @Suvrutt_Gurjar . The field with the expression is in the parent table. Just counting and keeping track of the number of records in the child table.

(Mncedisi Trinity Dewa) #5

@Aleksi_Alkio Thank you. How do I use this expression in my case? Where do I put the REFROWS expression? @Suvrutt_Gurjar its a real column

(Aleksi Alkio) #6

If you want to have a dynamic calculation, you need to use virtual column. Otherwise you won’t see the correct count if you don’t open that record and save it.

(Aleksi Alkio) #7

I believe you already have virtual list column in your table, correct?

(Mncedisi Trinity Dewa) #8

Thank you for the help. It is working now.