4. Database Entities

Entities are one of the most important concepts in Wasp and are how you define what gets stored in the database.

Wasp uses Prisma to talk to the database, and you define Entities by defining Prisma models in the schema.prisma file.

Since our Todo app is all about tasks, we'll define a Task entity by adding a Task model in the schema.prisma file:

schema.prisma

// ...

model Task {
    id          Int     @id @default(autoincrement())
    description String
    isDone      Boolean @default(false)
}

note

Read more about how Wasp Entities work in the Entities section or how Wasp uses the schema.prisma file in the Prisma Schema File section.

To update the database schema to include this entity, stop the wasp start process, if it's running, and run:

wasp db migrate-dev

You'll need to do this any time you change an entity's definition. It instructs Prisma to create a new database migration and apply it to the database.

To take a look at the database and the new Task entity, run:

wasp db studio

This will open a new page in your browser to view and edit the data in your database.

Click on the Task entity and check out its fields! We don't have any data in our database yet, but we are about to change that.