我有以下查询并且它有效。但由于它的堆积,处理需要非常长的时间。因此,我需要帮助才能更快地获得此查询。
SQL查询
在查询中,PRODUCT_ID 应替换为“ ”和产品 ID 号。
SELECT
b.order_id,
customer_meta.meta_value AS customer_id,
users.user_email,
qty_table.meta_value AS qty,
user_meta1.meta_value AS firstname,
user_meta2.meta_value AS lastname,
user_meta3.meta_value AS company,
user_meta4.meta_value AS address,
user_meta5.meta_value AS city,
user_meta6.meta_value AS postcode,
user_meta7.meta_value AS state,
user_meta8.meta_value AS user_phone
FROM
wp_woocommerce_order_itemmeta a,
wp_woocommerce_order_items b,
wp_postmeta customer_meta,
wp_users users,
wp_woocommerce_order_itemmeta qty_table,
wp_usermeta user_meta1,
wp_usermeta user_meta2,
wp_usermeta user_meta3,
wp_usermeta user_meta4,
wp_usermeta user_meta5,
wp_usermeta user_meta6,
wp_usermeta user_meta7,
wp_usermeta user_meta8
WHERE
a.meta_key = '_product_id'
AND a.meta_value = PRODUCT_ID
AND a.order_item_id = b.order_item_id
AND customer_meta.meta_key = '_customer_user'
AND customer_meta.post_id = b.order_id
AND user_meta1.meta_key = 'first_name'
AND user_meta1.user_id = users.id
AND user_meta2.meta_key = 'last_name'
AND user_meta2.user_id = users.id
AND user_meta3.meta_key = 'billing_company'
AND user_meta3.user_id = users.id
AND user_meta4.meta_key = 'billing_address_1'
AND user_meta4.user_id = users.id
AND user_meta5.meta_key = 'billing_city'
AND user_meta5.user_id = users.id
AND user_meta6.meta_key = 'billing_postcode'
AND user_meta6.user_id = users.id
AND user_meta7.meta_key = 'billing_state'
AND user_meta7.user_id = users.id
AND user_meta8.meta_key = 'billing_phone'
AND user_meta8.user_id = users.id
AND users.ID = customer_meta.meta_value
AND qty_table.meta_key = '_qty'
AND qty_table.order_item_id = b.order_item_id
ORDER BY user_meta3.meta_value ASC
我需要所有信息,因为我想列出已购买的给定产品的所有用户及其名字、姓氏、公司、地址、邮政编码等。因此查询本身可以工作,但会浪费处理时间。
我可以使用 max( CASE WHEN ... ... THEN ...END ) 作为 a_name 但我只知道如果使用左连接如何成功完成它。
关于如何让这个查询更好地运行有什么建议吗?