> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/better-auth/better-auth/llms.txt
> Use this file to discover all available pages before exploring further.

# Prisma

> Connect Better Auth to your database using Prisma ORM.

Prisma is a type-safe database toolkit for TypeScript. Better Auth ships a first-class Prisma adapter that supports SQLite, PostgreSQL, MySQL, CockroachDB, SQL Server, and MongoDB via Prisma.

## Installation

<Steps>
  <Step title="Install Prisma and the Prisma Client">
    <Tabs>
      <Tab title="npm">
        ```bash theme={null}
        npm install @prisma/client
        npm install --save-dev prisma
        ```
      </Tab>

      <Tab title="pnpm">
        ```bash theme={null}
        pnpm add @prisma/client
        pnpm add -D prisma
        ```
      </Tab>

      <Tab title="yarn">
        ```bash theme={null}
        yarn add @prisma/client
        yarn add --dev prisma
        ```
      </Tab>

      <Tab title="bun">
        ```bash theme={null}
        bun add @prisma/client
        bun add -d prisma
        ```
      </Tab>
    </Tabs>
  </Step>

  <Step title="Configure the adapter">
    Import `prismaAdapter` from `better-auth/adapters/prisma` and pass a `PrismaClient` instance:

    ```typescript title="auth.ts" theme={null}
    import { betterAuth } from "better-auth";
    import { prismaAdapter } from "better-auth/adapters/prisma";
    import { PrismaClient } from "@prisma/client";

    const prisma = new PrismaClient();

    export const auth = betterAuth({
      database: prismaAdapter(prisma, {
        provider: "postgresql", // "sqlite" | "postgresql" | "mysql" | "cockroachdb" | "sqlserver" | "mongodb"
      }),
    });
    ```
  </Step>
</Steps>

<Warning>
  Starting from Prisma 7, the `output` path field is required in `schema.prisma`. If you configured a custom output path (e.g. `output = "../src/generated/prisma"`), import `PrismaClient` from that location instead of `@prisma/client`.
</Warning>

## Configuration options

The `prismaAdapter` function accepts a `PrismaClient` instance and a config object:

| Option        | Type                                                                               | Description                                                                  |
| ------------- | ---------------------------------------------------------------------------------- | ---------------------------------------------------------------------------- |
| `provider`    | `"sqlite" \| "postgresql" \| "mysql" \| "cockroachdb" \| "sqlserver" \| "mongodb"` | The database provider. Required.                                             |
| `usePlural`   | `boolean`                                                                          | Set to `true` when your Prisma models use plural names. Defaults to `false`. |
| `debugLogs`   | `boolean`                                                                          | Enable verbose adapter logging. Defaults to `false`.                         |
| `transaction` | `boolean`                                                                          | Wrap multi-step operations in a Prisma transaction. Defaults to `false`.     |

## Prisma schema

The Better Auth CLI generates the required Prisma schema models based on your configuration and plugins.

```bash theme={null}
npx auth@latest generate
```

Schema generation is supported. Schema migration must be run separately through Prisma:

```bash theme={null}
npx prisma migrate dev
```

### Core schema

The schema below is the baseline required by Better Auth. The CLI generates this for you, including `@relation` directives needed for experimental joins.

```prisma title="schema.prisma" theme={null}
generator client {
  provider = "prisma-client-js"
}

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

model User {
  id            String    @id
  name          String
  email         String
  emailVerified Boolean   @default(false)
  image         String?
  createdAt     DateTime  @default(now())
  updatedAt     DateTime  @updatedAt
  sessions      Session[]
  accounts      Account[]

  @@unique([email])
  @@map("user")
}

model Session {
  id        String   @id
  expiresAt DateTime
  token     String
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt
  ipAddress String?
  userAgent String?
  userId    String
  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@unique([token])
  @@index([userId])
  @@map("session")
}

model Account {
  id                    String    @id
  accountId             String
  providerId            String
  userId                String
  user                  User      @relation(fields: [userId], references: [id], onDelete: Cascade)
  accessToken           String?
  refreshToken          String?
  idToken               String?
  accessTokenExpiresAt  DateTime?
  refreshTokenExpiresAt DateTime?
  scope                 String?
  password              String?
  createdAt             DateTime  @default(now())
  updatedAt             DateTime  @updatedAt

  @@index([userId])
  @@map("account")
}

model Verification {
  id         String   @id
  identifier String
  value      String
  expiresAt  DateTime
  createdAt  DateTime @default(now())
  updatedAt  DateTime @updatedAt

  @@index([identifier])
  @@map("verification")
}
```

<Note>
  The `@@map` directives keep Prisma model names in PascalCase while mapping to the lowercase table names Better Auth expects.
</Note>

## Applying migrations

After generating or editing your schema, run Prisma Migrate to apply the changes:

```bash theme={null}
npx prisma migrate dev --name init
```

For production deployments:

```bash theme={null}
npx prisma migrate deploy
```

## Experimental joins

Enabling joins allows Better Auth to fetch related data in a single query instead of multiple round-trips. Endpoints such as `/get-session` and `/get-full-organization` see 2-3x latency improvements with high-latency databases.

```typescript title="auth.ts" theme={null}
export const auth = betterAuth({
  experimental: { joins: true },
});
```

<Warning>
  Joins require `@relation` directives in your Prisma schema. Run `npx auth@latest generate` with the latest CLI to produce a schema that includes them.
</Warning>