如何获得所有产品的订单

Question

I have question about order table design in MySQL. I have ORDERS table like

Order_id | Customer_id | Total_Price | 
--------------------------------------

And on other side I have table PRODUCT

Product_id | Product_name | available_amount 
------------------------------------------

An order can contain several different Products. So,how can I change or update my database design like that I can efficiently access any Order with its all Products? Should I create seperate table names Order_details? Can you please help me?

Answer 1

Yep. You will want to create a separate table, like you mentioned, bringing together the Order and all of its Products, like so:

    Order_Product_id | Order_id | Product_id
    ----------------------------------------
    1                | 1        | 1
    2                | 1        | 3
    3                | 1        | 5
    4                | 2        | 3
    5                | 3        | 1
    6                | 3        | 2

Then you can get all the Products which are in an order like so:

Select op.Order_id, p.Product_id, p.Product_name 
FROM Product p 
JOIN Order_Product op ON op.Product_id = p.Product_id
WHERE op.Order_id = 1

Answer 2

you could see this

you have an order which have multi products and product could be in one or many orders then you have many-to-many relationship.

you just need to add new table with this schema order_products(id, order_id, product_id)

• id to make the row unique
• order_id foreign key of any order you have
• product_id foreign key of any product but in here it will be related to this order_id

Answer 3

Yes, the relation between orders and products are many to many, so you must break this relation by doing third table called order_products or order_details, this table has order_id, product_id as foreign keys. Also you should add quantity field, and sales_price field for this table. Also you shouldn't put the total_price in orders table, but you can calculate the total by sum(quantity*sales_price) fields in the third table.