Prisma Configuration
The central nervous system of your ORM. In Prisma v7+, prisma.config.ts replaces legacy configuration methods, offering full TypeScript support and programmatic control.
The Configuration Hub
Create a file named prisma.config.ts in your project root.
import { defineConfig, env } from "prisma/config";
import "dotenv/config";
export default defineConfig({
// 1. Schema Location
schema: "prisma/schema.prisma",
// 2. Migration & Seeding Strategy
migrations: {
path: "prisma/migrations",
seed: "tsx prisma/seed.ts",
},
// 3. Database Connection
datasource: {
url: env("DATABASE_URL"),
},
});Configuration API
| Property | Type | Description |
|---|---|---|
| schema | string |
Path to your schema.prisma file.
|
| migrations | object | Configures the output directory for SQL migrations and the command used to seed the database. |
| datasource | object |
Defines connection details. Supports url and shadowDatabaseUrl.
|
Environment Variables
Prisma v7 does not auto-load .env. You must explicitly import a loader.
import "dotenv/config";
Type Safety
Use the env() helper to ensure type-safe access to your environment strings.
url: env("DATABASE_URL")
# Shadow Database
Required for MySQL providers to detect schema drift accurately.
Why is this required?
Prisma Migrate creates a temporary "shadow" database to test your schema changes before applying them. Since MySQL does not support DDL transactions (rollback on error), this shadow DB ensures your main database doesn't get corrupted if a migration fails halfway.
Implementation
export default defineConfig({
// ... other options
datasource: {
url: env("DATABASE_URL"),
// Add the shadow database URL here
shadowDatabaseUrl: env("SHADOW_DATABASE_URL"),
},
});