我从 WordPress 中的 SQL 查询中得到 null

Question

我在尝试从 WordPress 中的特定元值获取数据时遇到问题，也就是说，当我在 sql 查询中执行“ WHERE AND (PM.meta_key= 'webm' and PM.meta_value= 'Chaturbate') ”时。 当我不使用 where 并获取所有数据时，它通常如下所示：

SELECT P.ID,
    MAX(CASE WHEN PM.meta_key = 'nombrem' THEN PM.meta_value END) AS nombrem,
    MAX(CASE WHEN PM.meta_key = 'generom' THEN PM.meta_value END) AS generom,
    MAX(CASE WHEN PM.meta_key = 'tiempom' THEN PM.meta_value END) AS tiempom,
    MAX(CASE WHEN PM.meta_key = 'urlm'    THEN PM.meta_value END) AS urlm,
    MAX(CASE WHEN PM.meta_key = 'imagenm' THEN PM.meta_value END) AS imagenm
FROM 
    K1nG_posts AS P
    LEFT JOIN K1nG_postmeta AS PM ON P.ID = PM.post_id 
WHERE 
    P.post_type = 'post' 
    AND (P.post_status = 'publish' OR P.post_status = 'private')
GROUP BY P.ID, P.post_date

但是，当我在名为“webm”的相应 meta_key 的 meta_value 中使用“ WHERE AND (PM.meta_key= 'webm' and PM.meta_value= 'Chaturbate') ”时，我得到了匹配记录但没有“select”信息，即null，如图所示：

SELECT P.ID,
    MAX(CASE WHEN PM.meta_key = 'nombrem' THEN PM.meta_value END) AS nombrem,
    MAX(CASE WHEN PM.meta_key = 'generom' THEN PM.meta_value END) AS generom,
    MAX(CASE WHEN PM.meta_key = 'tiempom' THEN PM.meta_value END) AS tiempom,
    MAX(CASE WHEN PM.meta_key = 'urlm'    THEN PM.meta_value END) AS urlm,
    MAX(CASE WHEN PM.meta_key = 'imagenm' THEN PM.meta_value END) AS imagenm
FROM 
    K1nG_posts AS P
    LEFT JOIN K1nG_postmeta AS PM ON P.ID = PM.post_id 
WHERE 
    P.post_type = 'post' 
    AND (P.post_status = 'publish' OR P.post_status = 'private')
    AND (PM.meta_key= 'webm' and PM.meta_value= 'Chaturbate')
GROUP BY P.ID, P.post_date

Answer 1

尝试使用此代码

 WHERE 
   P.post_type = 'post' 
   AND P.post_status = 'publish' OR P.post_type = 'post' AND P.post_status = 'private'

这基本上需要

P.post_type = 'post' AND P.post_status

作为 A 和

P.post_type = 'post' AND P.post_status = 'private'

就像B一样

A or B