Understanding Sequelize Op.
Are you a developer looking to enhance your understanding of Sequelize, a popular ORM for Node.js? If so, you’ve come to the right place. One of the most powerful features of Sequelize is its ability to perform operations on the database using the `Op` object. In this article, we will delve into the intricacies of Sequelize Op, exploring its various operations and how they can be utilized to manipulate your database efficiently.
What is Sequelize Op?
Sequelize Op, short for Operation, is a collection of methods that allow you to perform a wide range of operations on your database. These operations can be used to filter, sort, and manipulate data in various ways. By using Sequelize Op, you can write more concise and readable code, making it easier to manage your database interactions.
Types of Operations Provided by Sequelize Op
Sequelize Op offers a variety of operations that can be categorized into different types. Let’s take a closer look at some of the most commonly used operations:
| Operation | Description |
|---|---|
| eq | Equal to |
| neq | Not equal to |
| gt | Greater than |
| gte | Greater than or equal to |
| lt | Less than |
| lte | Less than or equal to |
| like | Pattern matching |
| notLike | Pattern matching with negation |
| in | Member of a set |
| notIn | Not a member of a set |
| between | Value is between two numbers |
| notBetween | Value is not between two numbers |
| isNull | Value is null |
| notNull | Value is not null |
| and | Logical AND |
| or | Logical OR |
These operations can be combined to create complex queries that can be used to retrieve, update, and delete data from your database.
Using Sequelize Op in Queries
Now that we have a basic understanding of the operations provided by Sequelize Op, let’s see how they can be used in queries. Consider the following example:
const { Sequelize, DataTypes } = require('sequelize');const sequelize = new Sequelize('sqlite::memory:');const User = sequelize.define('User', { name: { type: DataTypes.STRING, allowNull: false }, age: { type: DataTypes.INTEGER, allowNull: false }});(async () => { await sequelize.sync({ force: true }); await User.create({ name: 'John Doe', age: 30 }); await User.create({ name: 'Jane Doe', age: 25 }); const users = await User.findAll({ where: { age: { gte: 25, lte: 30 } } }); console.log(users);})();In this example, we have created a simple `User` model with `name` and `age` fields. We then use the `findAll` method to retrieve all users whose age is between 25 and 30. The `gte` and `lte` operations are used to filter the results based on the age criteria.
