Mysql数据库设计结构

Question

Which is a better db design when inserting records?

**Option 1.**
uid|itemid| qty | price | amount
1  |13| 2  |  100    |200

**Option 2.**
uid| itemid| qty | price | amount
1  |13| 1 | 100 | 100
2  |13| 1 | 100 | 100

In option 2 then retrieve rows via mysql query and calculate using id ...

Answer 1

It seems like you want to retain the original price of each item ordered. What I'd do is go with option 1, then create another column in your table that holds a string that identifies each item in the order.

For example, if I were selling fruit, a banana could have iZ as a unique key. And an apple could have 6U as a unique key. When a user places an order, these unique keys would be inserted into your new column. So when you see this column's data is iZ6U you'd know that the user ordered an apple and a banana.