如何在此查詢中使用MySql應用帶有WHERE CLAUSE的IF條件

Question

這是我的MySQL查詢，我在這個查詢中有一周的問題。 我不知道如何使用WHERE子句應用IF條件。

查詢：

SELECT
*,
IFNULL((SELECT ur.user_rating FROM user_rating ur 
WHERE ur.vid_id = v.id AND ur.user_id = '1000'),'NULL') AS user_rating
FROM videos v
WHERE WEEK(v.video_released_date) = WEEK(NOW())
AND  
v.`is_done` = 1
ORDER BY v.admin_listing ASC; 

我想要OR（我如何在where子句中應用這個條件？）

IF( WEEK(v.video_released_date) = WEEK(NOW()) , WEEK(NOW()) , WEEK(NOW())-1)
=
IF( WEEK(v.video_released_date) = WEEK(NOW()) , WEEK(NOW()) , WEEK(NOW())-1)

簡報

如果視頻發布日期已過，但與當前周不匹配則適用上周

我

當我像這樣嘗試自己時，他們會將整個數據歸還給我

SELECT
*,
IFNULL((SELECT ur.user_rating FROM user_rating ur 
WHERE ur.vid_id = v.id AND ur.user_id = '1000'),'NULL') AS user_rating
FROM videos v
WHERE IF(WEEK(v.video_released_date) = WEEK(NOW()),WEEK(NOW()),WEEK(NOW())-1)
= IF(WEEK(v.video_released_date) = WEEK(NOW()),WEEK(NOW()),WEEK(NOW())-1) 
AND  
v.`is_done` = 1
ORDER BY v.admin_listing ASC;

我在這個查詢中做錯了什么？

Answer 1

試試這個 -

    SELECT *,
           IFNULL((SELECT ur.user_rating FROM user_rating ur 
                   WHERE ur.vid_id = v.id AND ur.user_id = '1000'),'NULL') AS user_rating
    FROM videos v
    WHERE WEEK(v.video_released_date) = IF(WEEK(v.video_released_date) = WEEK(NOW()),WEEK(NOW()),WEEK(NOW())-1) 
    AND  v.is_done = 1
    ORDER BY v.admin_listing ASC;

Answer 2

好吧，看起來你通過這些IF比較x和x。

x = x“始終”為真。

Answer 3

使用CASE WHEN THEN ELSE END構造。 你可以閱讀更多關於它在這里的文檔。

SELECT *,
    IFNULL((SELECT ur.user_rating FROM user_rating ur 
        WHERE ur.vid_id = v.id AND ur.user_id = '1000'),'NULL') AS user_rating
    FROM videos v
    WHERE 
        WEEK(v.video_released_date) = 
            CASE WHEN WEEK(v.video_released_date) = WEEK(NOW()) 
            THEN WEEK(NOW()) ELSE WEEK(NOW())-1 END
    AND  
        v.`is_done` = 1
ORDER BY v.admin_listing ASC;