Как сгруппировать по пользователю и создать столбец со значениями в U-SQL?

Question

У меня есть следующий набор данных:

@employees = 
    SELECT * FROM 
        ( VALUES
        ("Noah",   "cell",   "030-0074321"),
        ("Noah",   "office", "030-0076545"),
        ("Sophia", "cell",   "(5) 555-4729"),
        ("Sophia", "office", "(5) 555-3745"),
        ("Liam",   "cell",   "(5) 555-3932"),
        ("Amy",    "cell",   "(171) 555-7788"),
        ("Amy",    "office", "(171) 555-6750"), 
        ("Amy",    "home",   "(425) 555-6238"),
        ("Justin", "cell",   "0921-12 34 65"),
        ("Justin", "office", "0921-12 34 67"),
        ("Emma",   (string)null, (string)null),
        ("Jacob",  "", ""),
        ("Olivia", "cell",   "88.60.15.31"),
        ("Olivia", "office", "88.60.15.32"),
        ("Mason",  "cell",   "(91) 555 22 82"),
        ("Mason",  "office", "(91) 555 91 99"), 
        ("Mason",  "home",   "(425) 555-2819"),
        ("Ava",    "cell",   "91.24.45.40"),
        ("Ava",    "office", "91.24.45.41"),
        ("Ethan",  "cell",   "(604) 555-4729"),
        ("Ethan",  "office", "(604) 555-3745"),
        ("David",  "cell",   "(171) 555-1212"),
        ("Andrew", "cell",   "(1) 135-5555"),
        ("Andrew", "office", "(1) 135-4892"),
        ("Jennie", "cell",   "(5) 555-3392"),
        ("Jennie", "office", "(5) 555-7293")
        ) AS T(EmpName, PhoneType, PhoneNumber);

Я пытался использовать пример карты, данный Microsoft ... но я не вижу, как изменить его для генерации столбцов.

@result =
    SELECT EmpName,
           String.Join(",", MAP_AGG(PhoneType, PhoneNumber).Select(p => String.Format("{0}:{1}", p.Key, p.Value))).Trim() AS PhoneNumbers
    FROM @employees
    WHERE !string.IsNullOrWhiteSpace(PhoneType)
    GROUP BY EmpName;

Какой результат:

Amy     cell:(171) 555-7788,home:(425) 555-6238,office:(171) 555-6750
Andrew  cell:(1) 135-5555,office:(1) 135-4892
Ava     cell:91.24.45.40,office:91.24.45.41

Я хотел бы получить:

User,   office,         cell,            home
Noah,   030-0076545,    030-0074321,     null
Sophia, (5) 555-3745,   (5) 555-4729,    null
Liam,   null,           (5) 555-3932,    null
Amy,    (171) 555-6750, (171) 555-7788,  (425) 555-6238
...

Заранее спасибо!

V.