mysql - 用 MySQL 中同一表的另一行中的值更新值

Question

我需要以下 SQL 的帮助：-

UPDATE `mg_catalog_category_entity_varchar` AS t1 INNER JOIN `mg_catalog_category_entity`
AS t2 ON t1.`entity_id`= t2.`entity_id`
SET t1.`value` = CONCAT('US Sports Goods ', t1.`value`, ' | My Site Name') 
WHERE t2.`path` LIKE '1/2642%' AND t2.`level` > 1 AND t1.`attribute_id` = 40

我的问题是语句中的t1.value字段CONCAT()需要提取t1.valueWHERE t1.attribute_id = 35，我正在努力弄清楚如何在CONCAT()语句中正确指定它。

Answer 1

尝试这个：

UPDATE `mg_catalog_category_entity_varchar` AS t1 INNER JOIN `mg_catalog_category_entity`
AS t2 ON t1.`entity_id`= t2.`entity_id`
SET t1.`value` = CONCAT('US Sports Goods ', (SELECT t3.`value` FROM `mg_catalog_category_entity_varchar` AS t3 WHERE t3.`attribute_id` = 35 LIMIT 1), ' | My Site Name') 
WHERE t2.`path` LIKE '1/2642%' AND t2.`level` > 1 AND t1.`attribute_id` = 40

Answer 2

尝试这个：

UPDATE `mg_catalog_category_entity_varchar` AS t1 
INNER JOIN `mg_catalog_category_entity` AS t2 ON t1.`entity_id`= t2.`entity_id`
INNER JOIN
(
   SELECT *
   FROM mg_catalog_category_entity_varchar
   WHERE `attribute_id` = 35
) AS t12 ON t2.entity_id = t12.entity_id 
SET t1.`value` = CONCAT('US Sports Goods ', t12.`value`, ' | My Site Name') 
WHERE t2.`path` LIKE '1/2642%' 
  AND t2.`level` > 1 
  AND t1.`attribute_id` = 40