将复杂的mysql SELECT转换为UPDATE

Question

我一直在尝试将复杂的SELECT查询转换为UPDATE查询，但我不断收到1064语法错误。

查询的目标是更新满足特定条件的某些行，但是连接和GROUP BY和HAVING语句使我现在的查询无法实现。我知道这不是正确的方法，但我无法发现解决方案应该是什么。如果有人能告诉我解决方案的方向，我会很棒！

我的查询（值不正确，但提供更多上下文）：

UPDATE products p
JOIN products_to_specifications pts ON pts.products_id = p.products_id
JOIN products_specifications ps ON ps.specifications_id = pts.specifications_id
SET p.products_image = 'file_name.jpg'
WHERE ps.specifications_name IN ('color') 
AND pts.content IN ('black')
AND p.products_manufacturer = 'BMW'
AND p.products_name = 'M5'
GROUP BY p.products_id
HAVING COUNT(DISTINCT ps.specifications_name) = 1 AND COUNT(DISTINCT pts.content) = 1

我的表结构：

表产品： products_id，products_image等（每种产品的基本信息相同）

table products_specifications： specifications_id，specifications_name

表products_to_specifications： products_id，specifications_id，content

我认为对于正确的解决方案，我将使用子查询，但我不确定如何构造查询

Answer 1

MySql在UPDATE语句中不支持GROUP BY。您可以通过将复杂查询作为派生表轻松更新，如下所示。

UPDATE products p, (SELECT p.products_id FROM products p
JOIN products_to_specifications pts ON pts.products_id = p.products_id
JOIN products_specifications ps ON ps.specifications_id = pts.specifications_id
WHERE ps.specifications_name IN ('color') 
AND pts.content IN ('black')
AND p.products_manufacturer = 'BMW'
AND p.products_name = 'M5'
GROUP BY p.products_id
HAVING COUNT(DISTINCT ps.specifications_name) = 1 AND COUNT(DISTINCT pts.content) = 1) AS t
SET p.products_image = 'file_name.jpg' WHERE p.products_id=t.products_id

希望这会对你有所帮助。