# Database Planning Activity TIME - 25 Minutes Get _as far as you can_ through the following activity: We'll be creating an Entity Relationship Diagram (ERD). You can use any app you like, but I recommend either: - [LucidChart](https://www.lucidchart.com/pages/) (better, but needs you to sign up) - [diagrams.net (formerly draw.io!)](https://app.diagrams.net/) (maybe not quite as good, but you can get started fast) Many drawing programs have something like this, though. Search for `erd` or `entity` or `table` or `resource`. Your task: use an ERD to map out a bookselling app! Questions to help you along: - What entities (resources, i.e., tables) do you need to sell books? - What attributes (columns) will they need? - What data types should those columns have? - What relationships will they have with each other? Are there any one-to-many or many-to-many relationships? If you finish, expand it. What if you open a second store? What about bookstore events?