Question

我正在尝试在Wordpress中设置警报，以便用户可以创建警报，以便在创建的新帖子（属性）与其设置条件（警报）匹配时通知他们。我的计划是使用两个帖子类型，一个用于属性，一个用于警报。然后，当保存属性发布时，它将执行以下示例查询：

SELECT 
    post_author
    FROM 
        wp_posts
    INNER JOIN wp_postmeta m1
        ON wp_posts.ID = m1.post_id
        AND m1.meta_key = 'a_property_type'
        AND m1.meta_value = 'flat'
    INNER JOIN wp_postmeta m2
        on wp_posts.ID = m2.post_id
        AND m2.meta_key = 'a_bedrooms_min' 
        AND m2.meta_value <= '2'
    INNER JOIN wp_postmeta m3
        on wp_posts.ID = m3.post_id
        AND m3.meta_key = 'a_bedrooms_max' 
        AND m3.meta_value >= '2'
    INNER JOIN wp_postmeta m4
        on wp_posts.ID = m4.post_id
        AND m4.meta_key = 'a_bathrooms_min' 
        AND m4.meta_value <= '2'
    INNER JOIN wp_postmeta m5
        on wp_posts.ID = m5.post_id
        AND m5.meta_key = 'a_bathrooms_max' 
        AND m5.meta_value >= '2'      
    INNER JOIN wp_postmeta m6
        on wp_posts.ID = m6.post_id
        AND m6.meta_key = 'a_garden' 
        AND m6.meta_value >= '1'        
    INNER JOIN wp_postmeta m7
        on wp_posts.ID = m7.post_id
        AND m7.meta_key = 'a_garage' 
        AND m7.meta_value >= '1'    
    INNER JOIN wp_postmeta m8
        on wp_posts.ID = m8.post_id
        AND m8.meta_key = 'a_parking' 
        AND m8.meta_value >= '1'        
    INNER JOIN wp_postmeta m9
        on wp_posts.ID = m9.post_id
        AND m9.meta_key = 'a_double_glazing' 
        AND m9.meta_value >= '1'    
    INNER JOIN wp_postmeta m10
        on wp_posts.ID = m10.post_id
        AND m10.meta_key = 'a_country' 
        AND m10.meta_value LIKE 'Scotland'        
    WHERE
        wp_posts.post_type = 'alerts'
        AND wp_posts.post_status = 'publish'
    GROUP BY 
       wp_posts.ID
    ORDER BY 
        wp_posts.post_date DESC

这可以并且确实返回与标准集匹配的属性，但是当我引入LIKE时，它确实使查询挂起。我正在使用默认的Wordpress表'wp_posts'和'wp_postmeta'。我已经尝试在列'meta_value'上设置一个索引，但因为它是一个'longtext'字段，它不允许我这样做。

有更好的解决方案可以做到这一点，还是可以更有效地编写查询？

由于

Answer 1

除了eggyal提供的内容之外，我也会在（post_id，meta_key，meta_value）上添加索引。如果这对您的查询没有帮助，我会尝试另外一件事。将除LIKE之外的所有元素预先包装到预先查询中，以便首先处理内部查询并返回一小组ID，然后加入LIKE条件。

假设您有1000个属性，但只有35个属性符合您的所有其他条件，并在亚秒级时间内解决。现在，您只有35条记录将被解析为您的额外LIKE条件。像

这样的东西

select
      wp.Post_Author
   from
      ( SELECT 
              post_id,
              post_author
           FROM 
              wp_posts
                 INNER JOIN wp_postmeta m1
                    ON wp_posts.ID = m1.post_id
                   AND m1.meta_key = 'a_property_type'
                 INNER JOIN the m2 through m9 
           WHERE
               type and status criteria ) as PreQuery
      INNER JOIN your m10 version
         on  PreQuery.Post_ID = m10.post_id
        AND ... rest of join condition

MySql Query在使用LIKE语句时挂起

1 个答案: