Question

SELECT
`wp_posts`.`post_title`
, `wp_posts`.`post_content`
, `wp_posts`.`post_type`
, `wp_posts`.`ID`
, `wp_posts`.`post_date`
, `wp_usermeta`.`user_id` AS `userID`
, `wp_usermeta`.`meta_value` AS `city`
, `wp_usermeta`.`meta_value` AS `state`
, `wp_users`.`fbconnect_userid` AS `fbuid`
FROM    `wp_posts`    
INNER JOIN `wp_emu_shop_reviews`         
    ON (`wp_posts`.`ID` = `wp_emu_shop_reviews`.`postID`)
LEFT JOIN `wp_users`                
    ON (`wp_emu_shop_reviews`.`wpUserID` = `wp_users`.`ID`)
LEFT JOIN `wp_usermeta`              
    ON (`wp_users`.`ID` = `wp_usermeta`.`user_id` AND `wp_usermeta`.`meta_key` ='location_city')
        OR(`wp_users`.`ID` = `wp_usermeta`.`user_id` AND `wp_usermeta`.`meta_key` ='location_state')
WHERE (`wp_posts`.`post_type` = "review"
AND `wp_posts`.`post_status` = "publish");

这部分不起作用的是让城市和州进入结果。当前查询将城市放入城市和州列。 Obv，最后一次加入是问题。

"This is the title" "blahblahblah"  "review"    "2074"  "2012-05-03 00:03:10"   "15"    "Redmond"   "Redmond"   "xxxxxxxx"

我很可能需要从wp_usermeta表中获取更多值，但我确信如果有人为我提出这个问题，我可以弄明白。

啊..根据Juris Malinens和Explosion Pills的建议，我认为这个查询有效。

SELECT
`wp_posts`.`post_title`
/* , `wp_posts`.`post_content` */
, `wp_posts`.`post_type`
, `wp_posts`.`ID`
, `wp_posts`.`post_date`
/* , `wp_usermeta`.`user_id` AS `userID` */
, um1.user_id AS `userID` 
, um1.meta_value AS `city`
, um2.meta_value AS `state`
, `wp_users`.`fbconnect_userid` AS `fbuid`
FROM    `wp_posts`    
INNER JOIN `wp_emu_shop_reviews`         
ON (`wp_posts`.`ID` = `wp_emu_shop_reviews`.`postID`)
LEFT JOIN `wp_users`                
ON (`wp_emu_shop_reviews`.`wpUserID` = `wp_users`.`ID`)
/*  LEFT JOIN `wp_usermeta`              
ON (`wp_users`.`ID` = `wp_usermeta`.`user_id` AND `wp_usermeta`.`meta_key` ='location_city') */
LEFT JOIN wp_usermeta um1 ON (`wp_users`.`ID` = `um1`.`user_id` AND um1.meta_key ='location_city') 
LEFT JOIN wp_usermeta um2 ON(`wp_users`.`ID` = `um2`.`user_id` AND um2.meta_key ='location_state')

WHERE (`wp_posts`.`post_type` = "review"
AND `wp_posts`.`post_status` = "publish");

Answer 1

查询无法知道您想要为特定行加入哪个元值，实际上在当前查询中它是不可能的（即它一次只能加入一个）。您需要加入wp_usermeta两次：

SELECT
    state.user_id AS userID
    state.meta_value AS state,
    city.meta_value AS city,
FROM
    wp_users
    JOIN wp_usermeta state ON (wp_users.ID = state.user_id
       AND state.meta_key = 'location_state')
    JOIN wp_usermeta city ON (wp_users.ID = city.user_id
       AND state.meta_key = 'location_city')

这是你需要做的事情的要点;只需添加其他联接和条件。

每个表AS别名值连接2个值

1 个答案: