The return type 'Null' isn't a 'Future<\_>', as required by the closure's context.
What the problem here ?

```dart
    void insertToDatabase() {
    database.transaction((txn){
      txn.rawInsert
        ('INSERT INTO tasks (title,date,time,status)VALUES("First task","0011","2430","New")')
          .then((value) {
        print('$value Inserted');
      }).catchError((error){
        print('error is ${error.toString()}');
      });

       return null;
    });
  }

```