mySQL:当meta_key不存在时将其插入表中

Question

好的，我希望在 mySQL 中针对 Wordpress 数据库运行循环查询。某些记录有一个自定义字段 [城市名称](例如:meta_key = 'sidebar' & meta_value = 'chicago')。问题是有些有这个自定义字段，而另一些则没有。我通过以下查询隔离了不存在的记录:

SELECT object_id 
FROM wp_term_relationships 
WHERE term_taxonomy_id = (
    SELECT term_id FROM wp_terms 
    WHERE name = 'Chicago') 
  AND object_id > 5911

结果集的object_id需要有

INSERT INTO wp_postmeta (meta_key, meta_value,post_id) 
VALUES ('sidebar','chicago',[object_id])

所以我的问题是如何将它们组合起来，以便 SELECT 循环遍历以对结果的每个 object_id 运行 INSERT。任何想法将不胜感激。谢谢-

Answer 1

你可以试试

INSERT INTO wp_postmeta (meta_key, meta_value,post_id)
SELECT 'sidebar','chicago', object_id 
  FROM wp_term_relationships 
 WHERE term_taxonomy_id = 
       (
          SELECT term_id 
            FROM wp_terms 
           WHERE name = 'Chicago'
       ) 
   AND object_id > 5911