New record in Child Tab of a UD Form

[JaneToo (Jane)]

Somebody please help. I can only add one row under child tab. When i try adding a second entry i am gettign below error

[aarong (Aaron Gulley)]

You need to auto increment the child record.

You can do this by using

Create a int variable… Mine is called excNum
Drop in a set variable

The expression I use

(Int32)((Db.UD101A
    .Where(r => r.Company == callContextClient.CurrentCompany && r.Key1 == ParentKey1)
    .Select(r => r.Number20)
    .DefaultIfEmpty(0))
    .OrderByDescending(u => u)
    .First())

Set Field 0

(excNum+1).ToString("D3")

D3 just adds three zeros in front e.g 001, 002, 003

Then just increment Number20 in the background

- excNum+1

Hope this helps.