MySQL multi table Association delete / update

During daily testing , You need to connect other tables and delete some dirty data , Write according to the normal query , Write delete statements like this ：

DELETE from `order` 
where id in (SELECT o.id from `order` o LEFT JOIN customer c on o.customer_id =c.id where o.customer_id is not null and c.id is null);

then … You can’t specify target table ‘order’ for update in FROM clause

intend ： Not first select Give some values in the same table , Again update This table , That is, you can't update the value of a field based on the value of a field .

ok ~~~

Baidu has studied how to solve the problem of deleting multi table connections .
I'm also confused here , Why is the writing method of the update table associated with multiple tables reading 、 I can't see the introduction when watching the video ？？？

--  Delete order The data table , Be careful ： Delete by alias 
DELETE o 
FROM `order` o
	LEFT JOIN customer c ON o.customer_id = c.id 
WHERE o.customer_id IS NOT NULL AND c.id IS NULL

--  Delete customer Table data , Be careful ： Delete by alias 
DELETE c 
FROM `order` o
	LEFT JOIN customer c ON o.customer_id = c.id 
WHERE o.customer_id IS NOT NULL AND c.id IS NULL

--  At the same time to delete order、customer Table data , Be careful ： Delete by alias 
DELETE o,c 
FROM `order` o
	LEFT JOIN customer c ON o.customer_id = c.id 
WHERE o.customer_id IS NOT NULL AND c.id IS NULL

By the way, I also studied how to update when connecting multiple tables ：

UPDATE wx_customer wc
LEFT JOIN `order` o ON wc.id = o.wx_customer_id 
SET o.wx_customer_id = NULL, wc.customer_id = NULL,wc.relate_wx_id = NULL 
WHERE	wc.id = "937680";

Here's a word ： Update of multi table connection , You can update two tables at the same time ~

When Baidu studies , Some bigwigs also use aliases .... I don't use this writing method very much , I won't post it here

Summarize the rules （ Otherwise, it's a little hard to remember ~）：

Whether it's SELECT、DELETE still UPDATE sentence , All of them are associated with multiple tables here .