I found your article very good, however there is a small problem, when I use method updateData() in ngOnInit(){this.userSource.updateData([{name: '1', email: '2', birthday : '3'}]);}
data table won't work
Glad you found it useful. I think the issue is because in the Datasource updateData method, we are not calling:
this.inititalDataSubject.next(res);
when the data passed is not an observable.