Yes/No function

A couple of questions:

let i := this; let s := (select Sessies); let n := Sessies.'S-nr'; if chosen('Coachees tab', [1]) = false then s = i; last(n); date(last(Sessies.Sessie)) end

In line 2 you do a select of the Sessies table and put the returned values in a variable (s).  Then in line 5 you set the variable (s) to equal the variable (i), which wipes the results of the select you just did. If you don't need the select I would recommend that you get rid of line 2. You want to try to reduce the use of select statements.

Line 3, shows me that you have a relationship field called Sessies. You then set a variable (n) to equal the array of data that is in the 'S-nr' field of all related records through the Sessies relationship. Then in line 6 you get the last item in the array. Then you do nothing with the variable. If you don't need the value then I would recommend removing any reference to (n) so you can make your code cleaner and faster.

In addition since you have relationship field you don't need to do a select. Another reason to get rid of Line2. Unless you need access to all records from Sessies not just related records.

So you could simplify your code to something like:

if OHW = false then
    date(last(Sessies.Sessie))
end

What kind of field is Sessie?

You could test out the if statement:

if OHW = false then "false" end

If this works then there is something up with your code getting the date.

Also know that a yes/no field has 3 states.
Yes, No and null.

Marjolijn said:
Unfortunately your suggested code would give me just the last date from the array of all sessions from all no-active clients.

 Looking back now, I have completely mis-read your code. (now where is that delete feature?)

Plus I don't know why the first code block formatted as a long string and not in lines.

Is there anyway you can upload a sample DB with dummy data?

I also tried cleaning up the code to:

if OHW = false then
    date(last(Sessies.Sessie))
end

And the same data is presented as with your code.

let i := this;
let s := (select Sessies);
let n := Sessies.'S-nr';
if OHW = false then
    s = i;
    last(n);
    date(last(Sessies.Sessie))
end

Line 5, you asks Ninox to compare the array in (s) to the rid in (i) and Ninox will always return "false" since an array with multiple values will probably never equal the rid of the current record. Then you do nothing with that information.

Line 6, you ask Ninox to get the last value in the array created in (n). Then you do nothing with that information.

Since Line 7 the last command that is the command that is displayed by Ninox. Now I know why you have the date() command around Sessie. Sessie is an appointment field.

The answer to your second part is you forgot the ":" in front of the "=" sign for Afspraken, line 7. Easy thing to do in Ninox. To set fields to a value you use ":=". If you have a plain "=" then you tell Ninox to evaluate if the field equals the value.

let s := this;
if Begeleidingsafspraken = null then
    let n := NR;
    let a := s.Email;
    let t := number(Begeleidingsafspraken.Nr);
    let newCA := (create Begeleidingsafspraken);
    Afspraken := true;
    newCA.(
        Coachees := s;
        t := n;
        Email := a
    );
    popupRecord(newCA)
else
    let myRec := (select Begeleidingsafspraken where Coachees = s);
    popupRecord(last(myRec))
end