Question

I’m making a game in PHP with MySQL and I was wondering what is the best way for me to store the items the users have purchased so it is linked with their account.

I plan to have a database with the items information in and the only ways I could think of doing it was:

1. Having a table for the users items in a serialised array of sort
2. Having masses of columns with a set amount of inventory space
3. Table with user_id and item_id and add a row every time they purchase an item, selecting the user_id relevant to the user to display their items

Which is best?

Answer 1

I think that you know at the beginning which items a user can buy, so in my opinion you should have three tables

• USERS table, in which you store user data (PRIMARY KEY is user_id)
• ITEMS table, in which you store items with their cost and data (PRIMARY KEY is item_id)
• USERITEMS table, in which you store every item bought by users. It should have two columns: user_id and item_id and you add a row every time a user buy an item.

This design lets you easily manage bought items and show every user its inventory.
More: you avoid wasting space in database duplicating unuseful informations