SQL 查询从一个表求和到另一个表

Question

I have two tables:

What I needs is SQL query that I can run via the SQL tab in phpMyAdmin, which will sum the "options_stock" from "table_options" based on the "product_id", and it will write that sum number into "main_stock" in "table_products" for the corresponding "product_id", so the "table_products" will look like this:

Thanks in advance.

Answer 1

Try the below - with update join

update table_product p  
join 
(select product_id, sum(options_stock) as options_stock from
table_options group by product_id
) o on p.product_id=o.product_id
set main_stock=options_stock