MySQL中的select count使用GROUP BY和重複計數每行

Question

在我已經打電話給我的表「賬單」類似下面

Bill   item   totalprice 

BILL_1  Fossil Watch 9000 
BILL_1  Fastrack  - 
BILL_1  Fastrack  - 
BILL_2  Woodlands  7000 
BILL_2  Woodlands  - 
BILL_3  Denim Shirt 9000 
BILL_3  Levis Jean - 

現在我需要的結果，如下面的結構

Bill   item   totalprice bill_count 

BILL_1  Fossil Watch 9000   3 
BILL_1  Fastrack  -   3 
BILL_1  Fastrack  -   3 
BILL_2  Woodlands  7000   2 
BILL_2  Woodlands  -   2 
BILL_3  Denim Shirt 9000   2 
BILL_3  Levis Jean -   2 

我用下面的查詢嘗試，

SELECT bill,item,totalPrice,COUNT(bill) FROM bills GROUP BY bill;

但我沒有得到預期的結果。

Answer 1

SELECT b.bill, b.item, b.totalPrice, tmp.cnt 
FROM bills b 
JOIN 
(
    select bill, COUNT(bill) as cnt 
    from bills 
    group by bill 
) tmp on tmp.bill = b.bill 

Answer 2

select bill,item,totalPrice,(SELECT 
COUNT(b1.bill) 
FROM 
bills AS b1 where b1.bill= b.bill 
GROUP BY bill) AS bill_count from bills AS b