計算特定ID的行數

Question

在第一個表中， album具有ID，在第二個表中， album album_details具有與album表id相關的sub_id

我需要顯示計數以獲取單獨的ID值。

SELECT DISTINCT B.SUB_ID, A . * , B.CONTENT_VALUE AS detail, 
(SELECT COUNT( ID ) 
FROM album_details WHERE A.ID = B.SUB_ID ) AS count
FROM album AS A, album_details AS B
WHERE A.WEBSITE_ID =  '571710720'
AND A.ID = B.SUB_ID
GROUP BY B.SUB_ID
LIMIT 0 , 30

現在count列的所有行都顯示40，但是需要為“ id = 4”顯示“ count” 6，為“ id = 2”顯示“ count” 3

Answer 1

SELECT count（ SUB_ID ），SUB_ID從album_details組按SUB_ID

Answer 2

假設第一個表是A，第二個表是B，則查詢將像這樣

select a.ID, count(b.SUB_ID) AS total
FROM A LEFT JOIN B ON A.ID = B.SUB_ID
Group by B.SUB_ID.

它可能會幫助您。 如果沒有，請詢​​問。

Answer 3

GROUP BY是您選擇的武器。

SELECT 
    a.ID,
    a.CONTENT_VALUE,
    COUNT(ad.ID)
FROM albums AS a
LEFT JOIN album_details AS ad ON a.ID = ad.SUB_ID
GROUP BY a.ID

隨時在GROUP BY之前添加您的WHERE 。

Answer 4

從album_details中選擇count（sub_id）作為count1，其中sub_id in（從專輯中選擇id）在哪里WHERE album.WEBSITE_ID ='571710720'AND album.ID = album_details.SUB_ID