我要 sql 查询更改会员状态

Question

My site has users with user_id and Customer_id. Default membership status is pending. I want a query to change membership status to active by checking details in the other 2 tables. If users have bought a membership plan, change their status to active.

step 1- I want to select all users with pending status from the "membership" table.

table name: membership

+---------+---------+
| user_id | status  |
+---------+---------+
|  1      | pending |
|  2      | active  |
|  3      | pending |
|  4      | pending |
|  5      | active  |
+---------+--------+

step 2- select customer_id of users from step 1.

table name: Customers
+---------+--------------+
| user_id | Customer_id  |
+---------+--------------+
|  1      | 17           |
|  2      | 18           |
|  3      | 21           |
|  4      | 25           |
|  5      | 29           |
+---------+--------------+

step 3- check if the selected customers from step 2 have ordered product_id 92. if yes then change status from pending to active in the "membership" table.

table name: orders

+-------------+------------+
| Customer_id | Product_id |
+-------------+------------+
|  21         | 85         |
|  25         | 92         |
|  29         | 99         |
+-------------+------------+

End Result must look like

    table name: membership

+---------+---------+
| user_id | status  |
+---------+---------+
|  1      | pending |
|  2      | active  |
|  3      | pending |
|  4      | active  |
|  5      | active  |
+---------+--------+

Answer 1

You can use update with join syntax:

update membership m
join Customers c on m.user_id = c.user_id
join orders o on c.Customer_id = o.Customer_id and o.Product_id = 92
set m.status = 'active'