Remove unmatched rows

[ppr (Peter Preuss)]

@jntrk
welcome to the forum

the case looks like it could be solved with the help of set operations

find some demo here:
DataTable_SetOperations.xaml (8.9 KB)

So we could do it with an except:
dtMain.AsEnumerable.Except(dtRemove.AsEnumerable, DataRowComparer.Default).CopyToDataTable

ensure following:

AsEnumerable is not a member of 'System.Data.Datatable'

Hi @lucas.mcgonagle EDIT 20.10 fixed this issue for newly created projects. You can fix it by adding the Assembly Reference manually in your xaml file: [image] Simply open the file in Notepad and create new line with this String: <AssemblyReference>System.Data.DataSetExtensions</AssemblyReference> Then reopen your project and the error should be gone. Please be careful while doing so and always keep a backup.

in case of empty results are to expect apply following pattern: