php - SQL查询同一个表中的多个值和多个键

Question

每个帖子都有两个帖子元:年和月(自定义)

我需要 SQL 查询来提取所有有

的帖子

wp_postmeta.meta_key = year AND wp_postmeta.meta_value = 2013

同时还有另一个 meta_key/meta_value 对

wp_postmeta.meta_key = month AND wp_postmeta.meta_value BETWEEN 1 AND 12 ;

SELECT * FROM wp_postmeta
WHERE (meta_key = 'agam_post_options_year' AND meta_value = 2013)
    OR (meta_key = 'agam_post_options_month' AND meta_value BETWEEN 0 AND 12 )
GROUP BY meta_value; 

这是我尝试过的东西，还有一些变体，但效果不大……这特别给了我一个包含 2013 年的帖子和 12 个帖子，月份字段为 1 或 ... 到 12

Answer 1

请用该表中的适当字段替换 _PUT_YOUR_POST_ID_FIELD_HERE_ 并尝试运行...

SELECT Y.meta_value, M.meta_value FROM wp_postmeta as Y
JOIN wp_postmeta AS M USING (_PUT_YOUR_POST_ID_FIELD_HERE_) 
WHERE (Y.meta_key = 'agam_post_options_year' AND Y.meta_value = 2013)
AND (M.meta_key = 'agam_post_options_month' AND M.meta_value BETWEEN 0 AND 12 )
GROUP BY Y.meta_value, M.meta_value;