prisma

Prisma Best Practices

Overview

Aspect	Recommendation
Version	Prisma 5.x
Database	PostgreSQL (recommended)
Type Safety	Full TypeScript integration
Migrations	Prisma Migrate

---

Schema Design

Basic Schema

// prisma/schema.prisma
generator client {
  provider = "prisma-client-js"
}

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

model User {
  id            String    @id @default(cuid())
  email         String    @unique
  name          String?
  passwordHash  String    @map("password_hash")
  role          Role      @default(USER)
  posts         Post[]
  profile       Profile?
  createdAt     DateTime  @default(now()) @map("created_at")
  updatedAt     DateTime  @updatedAt @map("updated_at")

  @@map("users")
  @@index([email])
}

model Post {
  id          String    @id @default(cuid())
  title       String
  content     String?
  published   Boolean   @default(false)
  author      User      @relation(fields: [authorId], references: [id], onDelete: Cascade)
  authorId    String    @map("author_id")
  categories  Category[]
  createdAt   DateTime  @default(now()) @map("created_at")
  updatedAt   DateTime  @updatedAt @map("updated_at")

  @@map("posts")
  @@index([authorId])
}

model Profile {
  id        String  @id @default(cuid())
  bio       String?
  avatarUrl String? @map("avatar_url")
  user      User    @relation(fields: [userId], references: [id], onDelete: Cascade)
  userId    String  @unique @map("user_id")

  @@map("profiles")
}

model Category {
  id    String @id @default(cuid())
  name  String @unique
  posts Post[]

  @@map("categories")
}

enum Role {
  USER
  ADMIN
}

---

Client Setup

Singleton Pattern

// lib/prisma.ts
import { PrismaClient } from '@prisma/client'

const globalForPrisma = globalThis as unknown as {
  prisma: PrismaClient | undefined
}

export const prisma =
  globalForPrisma.prisma ??
  new PrismaClient({
    log: process.env.NODE_ENV === 'development' 
      ? ['query', 'error', 'warn'] 
      : ['error'],
  })

if (process.env.NODE_ENV !== 'production') globalForPrisma.prisma = prisma