MongoDB and Prisma

Table of Contents

• Featured program
• Lesson 01: Setting up MongoDB and Prisma
• Lesson 02: Defining Data Models
• Lesson 03: CRUD Operations with Prisma
• Lesson Bonus: JS OOP

Featured program

Attention: Make sure your server is running and connected to your MongoDB Atlas cluster before interacting with the frontend.
follow the instructions in the lesson 01 to start the server.

Lesson 01: Setting up MongoDB and Prisma

We will be using MongoDB Atlas, a cloud-based database service.

Links

• MongoDB website
• Prisma website
• Prisma Docs - MongoDB Quickstart

Procedures

MongoDB & Prisma setup

1. Go to the MongoDB website and create/login to your account.
2. Create a new cluster in MongoDB Atlas.
3. Set your cluster configuration (e.g., cloud provider, region, cluster tier).
4. Wait for the cluster to be deployed.
5. Create the user and password for your database.
  //The database will be created with Prisma through schema.prisma
6. Go to the Prisma documentation and follow the MongoDB Quickstart guide.
  //Right now Prisma v7 doesn't support MongoDB, we will use Prisma v6.19
7. install required dependencies
   • npm install express

     If you don't have Express installed, run this command to install it.

   • npm install prisma@6.19.0 --save-dev
   • npm install @prisma/client@6.19.0
8. Creating prisma schema
   • npx prisma init --datasource-provider mongodb --output ../generated/prisma
     //We can remove prisma.configs.ts because we are not using the v7
9. In the schema.prisma file:
   • change the client->Provider from prisma-client to prisma-client-js.
   • change the db->Provider from postgresql to mongodb.
10. In VS Code, install the Prisma extensions:
    • Prisma extension by Prisma
    • Prisma insider extension by Prisma
11. Use the command:
    • npx prisma generate
    To generate the Prisma Client based on your schema.
12. Set the default version of prisma to 6.19.0 by using the command CTRL+SHIFT+P and selecting Pin the current workspace to Prisma 6
13. If the VS Code Still doesn't recognize the Prisma Client, use the command CTRL+SHIFT+P and selecting Reload Window
14. In the server.js add the lines to import and initialize the Prisma Client:
    • const { PrismaClient } = require('@prisma/client');
    • const prisma = new PrismaClient();
15. On MongoDB Atlas, create a new database and collection.
16. In your database, click in Connect and get the connection string.
17. Modify the .env file with your MongoDB connection string.
    Then before the querry string '?=', after the '/', change to /Users?
  //the /Users? set the default database to Users

Lesson 02: Defining Data Models

In this lesson, we will define our data models using the Prisma schema file. We will create a simple User model with fields for id, email, name, and age.

Procedures

1. Open the schema.prisma file in the prisma folder.
2. Define a new model called User with the following fields:
   • id: A unique identifier for each user (String, @id, @default(auto()), @map("_id"), @db.ObjectId)
   • email: The user's email address (String, @unique)
   • name: The user's name (String, optional)
   • age: The user's age (Int, optional)
3. After defining the model, run the command:
   • npx prisma db push
   This command will push your Prisma schema changes to your MongoDB database, creating the necessary collections and indexes based on your model definitions.

Model parameters

• @id: Marks the field as the primary key.
• @default(auto()): Automatically generates a unique value for the field (useful for IDs).
• @map("_id"): Maps the field to a different name in the database (in this case, MongoDB uses "_id" for primary keys).
• @db.ObjectId: Specifies that the field should be treated as a MongoDB ObjectId.
• @unique: Ensures that all values in this field are unique across the collection.
• @optional: Marks the field as optional, allowing it to be null.
• @relation: Defines a relationship between models.

Model typing

In Prisma, you can define the types of your model fields using the following data types:

• String: A sequence of characters.
• Int: A 32-bit integer.
• Float: A floating-point number.
• Boolean: A true/false value.
• DateTime: A date and time value.
• Json: A JSON object.
• Bytes: Binary data.
• Decimal: A decimal number (requires the Prisma Decimal.js library).
• Enum: A set of predefined values (you can define your own enums in the schema).


• We can use another model as a type for a field, creating a relationship between models.
  • @relation: Defines a relationship between models. For example, if you have a Post model that has a relation to the User model, you can define it like this:

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

  • You can also define a one-to-many relationship by using an array of another model. For example, if a User can have many Posts, you can define it like this:

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

  • Dont forget to push the changes with npx prisma db push
• we can check the database to see the changes reflected via prisma studio by using the command:
  • npx prisma studio

Lesson 03: CRUD Operations with Prisma

CRUD (Create, Read, Update, Delete) operations using the Prisma Client.

Procedures

1. Create: To create a new user, we can use the prisma.user.create() method. For example:

   const newUser = await prisma.user.create({
       data: {
           email: 'example@example.com',
           name: 'John Doe',
           age: 30
       }
   });
   

2. Read: To read users, we can use the prisma.user.findMany() method. For example:

   const users = await prisma.user.findMany();
   

3. Update: To update a user, we can use the prisma.user.update() method. For example:

   const updatedUser = await prisma.user.update({
       where: { id: 'userId' },
       data: { name: 'Jane Doe' }
   });
   

4. Delete: To delete a user, we can use the prisma.user.delete() method. For example:

   const deletedUser = await prisma.user.delete({
       where: { id: 'userId' }
   });