Prisma Documentation

Overview

Prisma is a next-generation ORM that consists of:

- **Prisma Client**: Auto-generated, type-safe query builder - **Prisma Migrate**: Declarative data modeling & migrations - **Prisma Studio**: GUI to view and edit data

Prisma supports PostgreSQL, MySQL, SQLite, SQL Server, MongoDB, and CockroachDB.

Schema Definition

prisma/schema.prisma

1// prisma/schema.prisma
2generator client {
3  provider = "prisma-client-js"
4}
5 
6datasource db {
7  provider = "postgresql"
8  url      = env("DATABASE_URL")
9}
10 
11model User {
12  id        String   @id @default(cuid())
13  email     String   @unique
14  name      String?
15  posts     Post[]
16  createdAt DateTime @default(now())
17  updatedAt DateTime @updatedAt
18}
19 
20model Post {
21  id        String   @id @default(cuid())
22  title     String
23  content   String?
24  published Boolean  @default(false)
25  author    User     @relation(fields: [authorId], references: [id])
26  authorId  String
27  createdAt DateTime @default(now())
28}

Installation

Quick Install

Terminal

1-amber-400">npm install prisma @prisma/client && -amber-400">npx prisma init

Requirements

Node.js 18+
Database (PostgreSQL, MySQL, SQLite, etc.)

Setup Steps

1Install Prisma: npm install prisma @prisma/client
2Initialize Prisma: npx prisma init
3Configure database URL in .env
4Define schema in prisma/schema.prisma
5Generate client: npx prisma generate
6Push schema: npx prisma db push

CRUD Operations

Prisma Client provides a fluent API for CRUD operations with full TypeScript support.

Database Queries

lib/db.ts

1400">import { PrismaClient } 400">from '@prisma/client';
2 
3400">const prisma = 400">new 300">PrismaClient();
4 
5// Create
6400">const user = 400">await prisma.user.300">create({
7  data: {
8    email: 'john@example.com',
9    name: 'John Doe',
10  },
11});
12 
13// Read
14400">const users = 400">await prisma.user.300">findMany({
15  where: { email: { contains: '@example.com' } },
16  include: { posts: 400">true },
17});
18 
19// Update
20400">const updated = 400">await prisma.user.300">update({
21  where: { id: user.id },
22  data: { name: 'John Updated' },
23});
24 
25// Delete
26400">await prisma.user.300">delete({
27  where: { id: user.id },
28});

Best Practices

Use a singleton pattern for PrismaClient in development
Define relations in your schema
Use transactions for multiple operations
Index frequently queried fields
Use select/include to limit data fetched

Common Pitfalls

⚠️Creating multiple PrismaClient instances

⚠️Not closing connections properly

⚠️N+1 query problems

⚠️Not using migrations in production

Code Snippets

Prisma Singleton

basic

Proper Prisma client setup for Next.js

TypeScript

1// lib/prisma.ts
2400">import { PrismaClient } 400">from '@prisma/client';
3 
4400">const globalForPrisma = globalThis 400">as unknown 400">as {
5  prisma: PrismaClient | 400">undefined;
6};
7 
8400">export 400">const prisma =
9  globalForPrisma.prisma ??
10  400">new 300">PrismaClient({
11    log: ['query'],
12  });
13 
14400">if (process.env.NODE_ENV !== 'production') {
15  globalForPrisma.prisma = prisma;
16}

Resources

Official Documentation

https://www.prisma.io/docs

GitHub Repository

https://github.com/prisma/prisma

Related Technologies

▲Next.js