Prisma ORM/Cheat sheet/MongoDB

Contents

Everything you need to know to use MongoDB effectively with Prisma ORM — from setup to modeling, querying, and working with embedded documents.
This guide brings together the flexibility of MongoDB and the type safety of Prisma. 🍃⚡

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⚙️ Setup

Install Prisma & MongoDB Driver

npm install prisma --save-dev
npm install @prisma/client

Initialize Prisma

npx prisma init

.env

DATABASE_URL="mongodb+srv://user:password@cluster0.mongodb.net/mydb?retryWrites=true&w=majority"

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🧱 Prisma Schema for MongoDB

Basic Example

generator client {
  provider = "prisma-client-js"
}

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

model User {
  id     String  @id @default(auto()) @map("_id") @db.ObjectId
  name   String
  email  String  @unique
  posts  Post[]
}

model Post {
  id        String  @id @default(auto()) @map("_id") @db.ObjectId
  title     String
  content   String?
  published Boolean  @default(false)
  authorId  String?  @db.ObjectId
  author    User?    @relation(fields: [authorId], references: [id])
}

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⚡ Prisma MongoDB Limitations

Prisma uses MongoDB’s document model under the hood — but with a relational flavor.

✅ Supported:

• Relations (via references)
• Embedded documents
• Arrays & JSON
• Unique indexes

🚫 Not Supported (as of Prisma 5.x):

• Transactions across collections
• Raw aggregation pipelines (must use $runCommandRaw)
• Complex multi-level relations

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🔄 Migrations

MongoDB doesn’t use SQL migrations — Prisma simulates them for schema synchronization.

Create Migration (in dev)

npx prisma db push

db push applies schema changes directly (no SQL migration files).

Reset Database

npx prisma migrate reset

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🧠 CRUD Operations

Create

const user = await prisma.user.create({
  data: {
    name: "Alice",
    email: "alice@example.com",
  },
});

Read

const users = await prisma.user.findMany();
const user = await prisma.user.findUnique({
  where: { email: "alice@example.com" },
});

Update

await prisma.user.update({
  where: { email: "alice@example.com" },
  data: { name: "Alice Cooper" },
});

Delete

await prisma.user.delete({
  where: { email: "alice@example.com" },
});

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🧩 Embedded Documents

MongoDB supports nested objects — Prisma maps them to JSON fields.

model Profile {
  id      String @id @default(auto()) @map("_id") @db.ObjectId
  userId  String @db.ObjectId
  user    User?  @relation(fields: [userId], references: [id])
  address Address
}

type Address {
  street String
  city   String
  zip    String
}

Create with embedded type:

await prisma.profile.create({
  data: {
    address: {
      street: "123 Maple Ave",
      city: "Toronto",
      zip: "H0H0H0",
    },
  },
});

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🔍 Filtering

const posts = await prisma.post.findMany({
  where: {
    published: true,
    title: { contains: "Mongo" },
  },
});

---

🧩 Relations

Connect Related Document

await prisma.post.create({
  data: {
    title: "Hello Mongo",
    author: {
      connect: { id: "66f4f0e..." },
    },
  },
});

Include Relations

await prisma.user.findMany({
  include: { posts: true },
});

Nested Writes

await prisma.user.create({
  data: {
    name: "Bob",
    posts: {
      create: [
        { title: "First Post" },
        { title: "Second Post" },
      ],
    },
  },
});

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🧮 Aggregations

MongoDB support for aggregations in Prisma is limited — but you can still use:

const stats = await prisma.user.aggregate({
  _count: true,
  _min: { name: true },
  _max: { name: true },
});

For advanced pipelines, use:

await prisma.$runCommandRaw({
  aggregate: "users",
  pipeline: [
    { $group: { _id: "$role", total: { $sum: 1 } } },
  ],
  cursor: {},
});

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🧰 Utility Queries

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🧮 JSON & Arrays

model Product {
  id     String   @id @default(auto()) @map("_id") @db.ObjectId
  tags   String[]
  config Json
}

Query Examples

await prisma.product.findMany({
  where: { tags: { has: "tech" } },
});

await prisma.product.findMany({
  where: { config: { path: ["color"], equals: "blue" } },
});

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🧾 Raw MongoDB Commands

For operations beyond Prisma’s ORM layer:

await prisma.$runCommandRaw({
  find: "users",
  filter: { email: "alice@example.com" },
});

Run inserts:

await prisma.$runCommandRaw({
  insert: "users",
  documents: [{ name: "Charlie", email: "c@x.com" }],
});

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🧭 Pagination & Sorting

const posts = await prisma.post.findMany({
  skip: 10,
  take: 5,
  orderBy: { createdAt: "desc" },
});

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🧠 Transactions (Limited)

MongoDB + Prisma supports single-database transactions only in clusters with replica sets.

await prisma.$transaction(async (tx) => {
  await tx.user.create({ data: { name: "Batch" } });
  await tx.post.create({ data: { title: "Atomic Post" } });
});

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🧰 Prisma Studio

Launch a GUI for MongoDB:

npx prisma studio

Opens http://localhost:5555
Browse, edit, and delete documents visually.

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🧩 Performance Tips

• Use indexes for frequently queried fields (@unique or @@index).
• Use lean models — MongoDB prefers fewer deeply nested documents.
• Avoid unnecessary include in queries.
• Batch operations with $transaction for consistency.
• Use db push instead of migrations for schema evolution.

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🧾 TL;DR Mind Map