Visualizing Prisma Schemas

Visualizing a database schema using an Entity-Relationship Diagram (ERD) tool is helpful in providing a clear and intuitive representation of the database structure, making it easier to understand the relationships and dependencies between different entities.

With Atlas, you can easily visualize your Prisma schema.

Getting started with Atlas and Prisma

To set up, follow along the getting started guide for Prisma and Atlas.

Project Setup

Prisma Schema

Assume we have the following Prisma schema.prisma file:

prisma/schema.prisma

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

model User {
  id       Int       @id @default(autoincrement())
  username String
  email    String    @unique
  posts    Post[]
  comments Comment[]
}

model Comment {
  id      Int    @id @default(autoincrement())
  content String
  user    User   @relation(fields: [userId], references: [id])
  userId  Int
  Post    Post?  @relation(fields: [postId], references: [id])
  postId  Int?
}

model Post {
  id       Int       @id @default(autoincrement())
  title    String
  content  String
  user     User      @relation(fields: [userId], references: [id])
  userId   Int
  comments Comment[]
}

Above we see three types: User, Post and Comment. The User model includes fields for username and email. The Post model contains fields for title and content, referencing the user who created it and allowing for multiple comments. The Comment model includes the content of the comment and references both the user and the post.

Config File

Before we begin testing, create a config file named atlas.hcl.

In this file we will create an environment, specify the source of our schema, and a URL for our dev database.

atlas.hcl

data "external_schema" "prisma" {
  program = [ 
    "npx",
    "prisma",
    "migrate",
    "diff",
    "--from-empty",
    "--to-schema-datamodel",
    "prisma/schema.prisma",
    "--script"
  ]
}

env "local" {
  src = data.external_schema.prisma.url
  dev = "docker://postgres/16/dev?search_path=public"
}

Visualizing

Now that we are all setup, we can visualize our Prisma models by running the inspect command with the -w flag:

atlas schema inspect --env local --url env://src -w

If you are not logged in, the output should be similar to:

? Where would you like to share your schema visualization?:
  ▸ Publicly (gh.atlasgo.cloud)
  Your personal workspace (requires 'atlas login')

Our browser should open:

Amazing! Now you can easily view and share your schema. Logged in users can also privately create schemas and save them for future use.