Prisma schema

VS Code

Syntax highlighting for PSL is available via a VS Code extension (which also lets you auto-format the contents of your Prisma schema and indicates syntax errors with red squiggly lines). Learn more about setting up Prisma in your editor.

GitHub

PSL code snippets on GitHub can be rendered with syntax highlighting as well by using the .prisma file extension or annotating fenced code blocks in Markdown with prisma:

```prisma
model User {
  id        Int      @id @default(autoincrement())
  createdAt DateTime @default(now())
  email     String   @unique
  name      String?
}
```

Accessing environment variables from the schema

Environment variables can be accessed using the env function:

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

In version 2.7.0 and later, you can expand variables using the format specified by dotenv-expand. This is useful when dealing with PaaS or similar products. such as Heroku):

# .env
DATABASE_URL=postgresql://test:test@localhost:5432/test
DATABASE_URL_WITH_SCHEMA=${DATABASE_URL}?schema=public

There are a few limitations with env at the moment:

• It is not possible to use environment variables for the provider argument in datasource and generator definitions.

Using .env files

For many developer tools, it has become a good practice to define environment variables using .env files. The Prisma CLI looks for .env files, in order, in the following locations:

1. In the root folder of your project (./.env)
2. From the same folder as the schema specified by the --schema argument
3. From the same folder as the schema taken from "prisma": {"schema": "/path/to/schema.prisma"} in package.json
4. From the ./prisma folder

If a .env file is located in step #1, but additional, clashing .env variables are located in steps #2 - 4, the CLI will throw an error. For example, if you specify a DATABASE_URL variable in two different .env files, you will get the following error:

You are trying to load env variables which are already present in your project root .env
  Root: C:\Prisma\Sandbox\mssql\.env
  Prisma: ./prisma/.env
  Env Conflicts:
          DATABASE_URL
You can fix this by removing the .env file from "./prisma/.env" and move its contents to your .env file at the root "C:\Prisma\Sandbox\mssql\.env" 
The following table describes where the Prisma CLI looks for the `.env` file:
 **Command**                                     | **Schema file location**                                                        | **`.env` file locations checked, in order**    |
 :---------------------------------------------- | :------------------------------------------------------------------------------ | :--------------------------------------------- |
 `prisma [command]`                              | `./prisma/schema.prisma`                                                        | `./.env`<br />`./prisma/.env`                                |
 `prisma [command] --schema=./a/b/schema.prisma` | `./a/b/schema.prisma`                                                           | `./.env`<br />`./a/b/.env`<br />`./prisma/.env` |
 `prisma [command]`                               | `"prisma": {"schema": "/path/to/schema.prisma"}`                                | `.env`<br /> `./path/to/schema/.env`<br />`./prisma/.env` |
 `prisma [command]`                              | No schema (for example, when running `prisma introspect` in an empty directory) | `./.env`<br />`./prisma/.env`                                |
Any environment variables defined in that `.env` file will automatically be loaded when running a Prisma CLI command.
> **Warning**: Do not commit your `.env` files into version control.
Refer to the `dotenv` documentation for information about [what happens if an environment variable is defined in two places](https://www.npmjs.com/package/dotenv#what-happens-to-environment-variables-that-were-already-set).
#### Example: Set the `DATABASE_URL` environment variable in an `.env` file
It is common to load your database connection URL from an environment variable:
```prisma
// schema.prisma
datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

You can set the DATABASE_URL in your .env file:

# .env
DATABASE_URL=postgresql://test:test@localhost:5432/test?schema=public

When you run a command that needs access the database defined via the datasource block (for example, prisma introspect), the Prisma CLI automatically loads the DATABASE_URL environment variables from the .env file and makes it available to the CLI.

Using environment variables in your code

If you want environment variables to be evaluated at runtime, you need to load them manually in your application code (for example, by using dotenv):

import * as dotenv from 'dotenv'
dotenv.config() // Load the environment variables
console.log(`The connection URL is ${process.env.DATABASE_URL}`)

Manage .env files manually

You can use dotenv-cli if you want to:

• Use multiple .env files
• Use .env files from a location that the Prisma CLI does not check by default