MySQL:如何根据表2中的列的条件更新表1中的列

Question

所以我有两个表，名为:product_to_category 和 product_description

product_to_category (product_id, category_id)

product_description (product_id, description)

我想按 category_id 编号更新列 description。

Answer 1

我认为下面的查询会对您有所帮助

Update product_description  set description = b.category_id 
From product_description a Inner Join product_to_category  b
ON a. product_id = b. product_id