我大部分时间都在试图弄清楚这一点,所以我想是时候问专家了:我正在尝试在 WordPress 之外访问我的 WordPress 数据库,所以我正在编写查询以从有点复杂的 WordPress 中获取输出数据库。
数据库中有几个表使用 meta_values 和 meta_keys 在多行中存储有关帖子或用户的数据。
例如,这里有四个我需要从中提取的表:
表:wp_postmeta
post_id | meta_key | meta_value
---------+-----------------+------------
2001 | _customer_user | 3
2001 |order_description| smith
2001 | _order_total | 300
表:wp_posts
ID | post_type | post_status
----+-----------+------------
2001| shop_order| publish
表:wp_term_relationships
object_id | term_taxonomy_id
----------+-----------------
2001 | 190
表:wp_usermeta
user_id | meta_key |meta_value
---------+-----------------+----------
3 | first_name | Andy
3 | last_name | Mccormick
我有这个查询可以很好地在一行中显示订单号 (post_id) 客户 ID、订单描述和订单总数:
SELECT wp_posts.ID, wp_posts.post_title,ot.meta_value as total,od.meta_value as order_desc, cu.meta_value as customer
FROM wp_posts
LEFT JOIN wp_postmeta AS ot ON (wp_posts.ID = ot.post_id AND ot.meta_key='_order_total')
LEFT JOIN wp_postmeta AS od ON (wp_posts.ID = od.post_id AND od.meta_key='order_description')
LEFT JOIN wp_postmeta AS cu ON (wp_posts.ID =cu.post_id AND cu.meta_key='_customer_user')
LEFT JOIN wp_term_relationships ON wp_posts.ID = wp_term_relationships.object_id
WHERE wp_posts.post_type = 'shop_order'
AND wp_posts.post_status = 'publish'
AND wp_term_relationships.term_taxonomy_id = '190'
GROUP BY wp_posts.ID ORDER BY wp_posts.post_date DESC"
然而,在另一个领域,我想按姓名列出客户,而不仅仅是按 ID,所以我试图从 wp_usermeta 表中获取他们的名字和姓氏,如下所示:
SELECT wp_posts.ID, cu.meta_value as customer, fn.meta_vale as fname, ln.meta_value as lname
FROM wp_posts
LEFT JOIN wp_postmeta AS cu ON (wp_posts.ID = cu.post_id AND cu.meta_key='_customer_user')
LEFT JOIN wp_usermeta AS fn ON (cu.meta_key = fn.user_id AND fn.meta_key='first_name')
LEFT JOIN wp_usermeta AS ln ON (cu.meta_key = ln.user_id AND ln.meta_key='last_name')
LEFT JOIN wp_term_relationships ON wp_posts.ID = wp_term_relationships.object_id
WHERE wp_posts.post_type = 'shop_order'
AND wp_posts.post_status = 'publish'
AND wp_term_relationships.term_taxonomy_id = '190'
GROUP BY wp_posts.ID ORDER BY wp_posts.post_date DESC;
我也尝试过: LEFT JOIN wp_usermeta AS fn ON ((cu.meta_key='_customer_user') = fn.user_id AND fn.meta_key='first_name') 以及许多其他子查询等。
显然,我现在在 SQL 查询中高于我的薪酬等级,所以任何帮助都会很棒。谢谢!