我有一个基于WooCommerce会员的网站，使用了Teams for WooCommerce会员扩展。尽管有庞大的用户群体（> 70,000用户），95%的时间它表现得非常好。我们每天接待约10,000个访问，响应时间在一秒以下。

在用户需要完成培训的旺季期间，由于并发未缓存请求的负载，网站可能会崩溃。

使用Query Monitor工具，有一个查询引起了注意：0.0375秒（平均值小于0.0050秒）。这个查询检查以下内容：

1. 当前用户是否是具有活跃订阅的团队的成员？

2. 他们是否有权限查看此文章？

以下是查询本身：

SELECT wp_posts.*
    FROM wp_posts
    LEFT JOIN wp_postmeta _teams_pm
    ON wp_posts.ID = _teams_pm.post_id
    AND _teams_pm.meta_key = '_member_id'
    AND _teams_pm.meta_value = 2
    LEFT JOIN wp_usermeta _teams_um
    ON _teams_um.user_id = _teams_pm.meta_value
    AND _teams_um.meta_key = CONCAT( '_wc_memberships_for_teams_team_', wp_posts.ID, '_role' )
    WHERE 1=1
    AND ((wp_posts.post_type = 'wc_memberships_team'
    AND (wp_posts.post_status = 'publish'
    OR wp_posts.post_status = 'acf-disabled'
    OR wp_posts.post_status = 'private')))
    AND ( _teams_um.meta_value    IN('manager', 'member')
    OR wp_posts.post_author = 2 )
    ORDER BY wp_posts.post_date DESC

它被以下调用：

"WP_Query->get_posts()
wp-includes/class-wp-query.php:3111
WP_Query->query()
wp-includes/class-wp-query.php:3542
WP_Query->__construct()
wp-includes/class-wp-query.php:3653
SkyVergeWMTTeams_Handler->get_teams()
wp-content/plugins/woocommerce-memberships-for-teams/src/Teams_Handler.php:446
wc_memberships_for_teams_get_teams()
wp-content/plugins/woocommerce-memberships-for-teams/src/Functions/Teams.php:100
ctz_membership_get_user_team_id()
wp-content/plugins/core-functionality/temp/wc_teams.php:603"

有人有任何关于如何加快此查询速度的索引的想法吗？我对SQL不够熟悉，不知道最佳索引位置在哪里。

我们预计周一会有一个大的峰值，所以我希望在本周末网站比较空闲的时候能有所准备。

提前感谢！

编辑：explain的输出，前缀和数据库名称已匿名化：

+----+-------------+---------------+------------+-------+------------------------------+------------------+---------+----------------------------------------------+------+----------+---------------------------------------+
| id | select_type | table         | partitions | type  | possible_keys                | key              | key_len | ref                                          | rows | filtered | Extra                                 |
+----+-------------+---------------+------------+-------+------------------------------+------------------+---------+----------------------------------------------+------+----------+---------------------------------------+
|  1 | SIMPLE      | wp_posts | NULL       | range | type_status_date,post_author | type_status_date | 164     | NULL                                         | 5556 |   100.00 | Using index condition; Using filesort |
|  1 | SIMPLE      | _teams_pm     | NULL       | ref   | PRIMARY,meta_key,meta_value  | PRIMARY          | 1030    | dbname.wp_posts.ID,const    |    1 |   100.00 | Using where                           |
|  1 | SIMPLE      | _teams_um     | NULL       | ref   | PRIMARY,meta_key             | PRIMARY          | 1030    | dbname._teams_pm.meta_value,func |    1 |   100.00 | Using where                           |
+----+-------------+---------------+------------+-------+------------------------------+------------------+---------+----------------------------------------------+------+----------+---------------------------------------+
3 rows in set, 4 warnings (0.00 sec)