Using CountRows to identify a collection entry and prevent duplicates

[LeeB_CDN]

 Hello, Super smart people

I am struggling with using CountRows()+1 when adding data to a collection. I have the function working correctly in that I can create multiple records in the collection, but if I delete an earlier entry and add a new one, I end up getting a duplicate ID number, (see code below) trying to ensure a unique ReportID value is maintained for each record (regardless of their order of creation). 

Collect(colUnsavedRecords,{ReportID:CountRows(colUnsavedRecords)+1,ReportDate:DatePicker1.SelectedDate,Time:Now()

 Here are the 3 sequential entries: 

And here is after I deleted the second entry and added another new record. 

  

Haven't had much luck using an If statement, or assigning the ReportID to a variable.. 

Any thoughts?

Thank you in advance! 

LeeB

[PTBBSolutions]

@LeeB_CDN 

When you remove a record from the collection, the countrows of the collection = 2. 2+1 = 3 - it does exactly what you are telling it to do. I would suggest to create a variable counter e.g. Set(Var_Number,0) on app start for example and instead of using countrows +1, use Var_Number+1.

Let me know if you need more detailed explanation.

If this solved you problem, please accept it as a solution.

[LeeB_CDN]

Yes, that makes total sense... The issue I foresee with using a global variable for this, is the potential for a duplicate record if the app is closed and restarts, whereby Var_Number, will be zero again and just start adding duplicate records? 

I'm saying this because I am storing collections into a local file to be recalled at a later date and completed... With the potential for the app to be closed and reopened. 

[PTBBSolutions]

OK then, on app start create a variable based on the max ID currently available (I am not sure how you understand if a session has ended in a happy path or it encountered an issue). After that apply the same logic => Variable + 1

[LeeB_CDN]

This is intriguing! Tell me more... Do you have a syntax example to illustrate? There would never be more than say 25 "incomplete" records in the local device at any time... so 25 cold be the max ID.

[PTBBSolutions]

Where do you store your collection results for the moment? Meaning, if the app restarts (or something like that), where is the collection results stored?

[LeeB_CDN]

SaveData(colUnsavedRecords,"localUnsavedRecords");

[PTBBSolutions]

Set(Var_Number,Max(LoadData(colUnsavedRecords,"localUnsavedRecords")).ID) - this way you will retrieve the max ID from your already stored collection and continue from there.

[LeeB_CDN]

That is genius PTTBSolutions! I am going to implement and test right now... 

[PTBBSolutions]

@LeeB_CDN 

Please accept it as a solution if it works for you 🙂