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Krishna Bhamare
Krishna Bhamare

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The Sequelize library simplifies developer life.

  • Sequelize is an Object-Relational Mapping (ORM) library for Node.js that allows developers to interact with databases using JavaScript. It supports multiple database systems, including MySQL, PostgreSQL, SQLite, and MSSQL, and provides a powerful set of tools for working with data, including querying, validation, and associations. It can be used to perform common database operations, such as inserting, updating, and retrieving data, without having to write raw SQL statements.

  • To use Sequelize, you would first need to install it in your Node.js project using npm:

npm install sequelize
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Then, you would need to create a connection to your database by importing the library and initializing it with the connection details, like this:

const Sequelize = require('sequelize');
const sequelize = new Sequelize('database', 'username', 'password', {
  host: 'localhost',
  dialect: 'mysql'
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Once the connection is established, you can define your data models using the define method on the sequelize instance. For example, to define a User model with a name and email field:

const User = sequelize.define('User', {
  name: Sequelize.STRING,
  email: Sequelize.STRING
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You can use the define method to define relationship between the tables.

  • After defining your models, you can then use the sync method to create the corresponding tables in the database:
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To perform CRUD operations, you can use the various methods provided by the model instances, such as create, findAll, update, and destroy.

  • For example, to create a new user:
User.create({ name: 'John Doe', email: '' });
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  • To retrieve all users from the database:
User.findAll().then(users => {
  // do something with the users
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  • These are just a few examples of how to use Sequelize. It's a powerful library with many other features and options for working with databases in Node.js. You can refer to the official documentation for more information and examples.


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