How to get the customer id when creating the customer and order at the same time?

Question

I am trying to understand the database design for an e-commerce site. I am having trouble understanding on what to do in the following situation. Say the user creates an account for the first time, and makes an order. I can write php code which will add the user_id (primary-key), first name & last name. But what if I want to add the user_id in the orders table (user_id in the orders tables is a foreign key). How do I get the value, as the user_id in the customers table is auto incrementing?

Answer 1

您是否使用两个表来存储用户详细信息，另一个用于下订单？（更好）如果这样，我的建议是使用用户名（而不是名字或姓氏）作为主键，并将用户名存储为SESSION变量登录并为每个订单在订单表中添加用户名以及订单详细信息

Answer 2

有两种方法可以执行此操作，您可以通过LAST_INSERT_ID()访问新生成的user_id并在后续事务中使用它，也可以将其存储在会话中，稍后在插入Orders表时使用它。