Using Raw SQL with Sequelize ORM

Introduction: What Are Sequelize ORM and Raw SQL?

In modern JavaScript applications, Object-Relational Mapping (ORM) libraries are commonly used to manage database operations more easily. Sequelize ORM is one of the most preferred ORMs in the Node.js environment. Working compatibly with many databases such as SQLite, PostgreSQL, and MySQL, Sequelize provides a model-based structure; however, in some cases, built-in functions may fall short, and more flexible, advanced queries may be needed. At this point, raw SQL support comes into play and allows developers to write and run SQL queries directly.

How to Use Raw SQL with Sequelize?

Thanks to using raw SQL with Sequelize ORM, you can write complex queries directly in SQL, going beyond the limitations provided by ORM for performance optimization or advanced operations. Sequelize provides safe and easy execution of your native SQL queries with the sequelize.query() function.

Basic Raw SQL Query Example

const { Sequelize } = require('sequelize');
const sequelize = new Sequelize('sqlite::memory:');

(async () => {
  // Get all users from table
  const [results, metadata] = await sequelize.query("SELECT * FROM users");
  console.log(results);
})();

In the code above, all data is fetched from the "users" table with the sequelize.query() function. The results return to two different variables: results (data rows) and metadata (additional information about the query).

Using Parameterized Raw SQL and Security

// Example of a parameterized query (safe for SQL Injection)
const userId = 1;
const [user] = await sequelize.query(
  "SELECT * FROM users WHERE id = :id",
  {
    replacements: { id: userId },
    type: Sequelize.QueryTypes.SELECT
  }
);
console.log(user);

By working with parameters, you can protect against SQL injection attacks. The value from the replacements object is automatically inserted into :id. Also, with type, it is possible to specify the type of result returned (for example, SELECT, UPDATE).

Advantages and Disadvantages of Using Raw SQL with Sequelize ORM

Using raw SQL with Sequelize ORM provides great advantages in performance-demanding queries and enables special operations not directly supported by ORM. However, in this approach, you must be careful of errors and security risks, and provide sufficient logging when necessary. Also, incompatibilities with the model-based structure may occur, so raw SQL should be preferred only when absolutely necessary.

Conclusion: Powerful and Flexible Control with Raw SQL

Using raw SQL with Sequelize ORM offers practical solutions and provides developers with great flexibility. It is a critical tool both for creating advanced queries and for optimizing application performance. When implemented correctly and safely, it will provide you with significant advantages in modern Node.js projects.