.png)
Table of Contents
What is Sequelize and Why Use It?
When working with SQL databases in Node.js, Sequelize is one of the most popular ORM (Object-Relational Mapping) tools available. But why should you use Sequelize?
Sequelize simplifies database interactions by allowing you to work with JavaScript objects instead of writing raw SQL queries. This makes your code more readable and easier to maintain.
Using Sequelize, you can connect to a MySQL database, define models, and interact with your database in a clean, JavaScript-centric way. So, if you're dealing with a realtime database in Node.js, Sequelize can make your life a lot easier.
How to Synchronize Your Database with Sequelize?
Do you need to change a field name or make other modifications to your database table? With Sequelize, it's straightforward.
First, in your `index.js` file, locate the following code:
db.sequelize.sync({ force: false })
.then(() => {
console.log('Database is synchronized');
})
.catch(err => {
console.log(err);
});
By default, force: false is set, which means that if the table already exists, it won't be recreated. However, if you want to apply changes to your table (like changing a field name), set force: true.
Why? Because setting force: true will drop the existing table and recreate it based on your current model definitions. But be careful—this will also erase all data in the table. So, after making your changes, don't forget to set force: false.
How to Handle Data from the Frontend and Store It in the Database?
Handling data from a form on your website and storing it in your SQL database in Node.js can be done using a combination of EJS, Sequelize, and Express.js. Here's how:
Step 1: Creating the Form
Start by creating a form in your EJS file (e.g., createBlog.ejs) and rendering it using Express.js:
app.get('/create', (req, res) => {
res.render('createBlog.ejs');
});
When a user visits the /create path, your EJS form will be displayed.
Step 2: Handling Form Data
To handle the data submitted from the form, use the POST method in Express:
app.post('/create', (req, res) => {
console.log(req.body);
});
This code checks if the form data is being received correctly.
If your output is "undefined," it means the server isn't reading the data correctly. To fix this, ensure you're using the appropriate middleware to parse incoming data. If your frontend and backend are part of the same application (monolithic architecture), use:
app.use(express.urlencoded({ extended: true }));
For microservices architecture, where the frontend and backend are separate, use:
app.use(express.json());
Step 3: Storing Data in the Database
After confirming that data is being received, store it in the database using Sequelize's create method:
const { title, subtitle, description, image } = req.body;
await blogs.create({ title, subtitle, description, image });
res.send('Data Added In Database');
Make sure to import the `blogs` variable from your `index.js` file into `app.js`:
const { blogs } = require('./model/index.js');
If `blogs` is not correctly imported, you might encounter a type error when calling `blogs.create`. To resolve this, double-check your import statements and ensure everything is correctly configured.
Tips of the Day
Tip: Use Fake Filters Extension for Testing Purpose
When testing your application, use fake filters to simulate different data scenarios without having to manually enter data. This can help you identify potential issues and make testing more efficient.Link : Fake Filter
Conclusion
Working with a real-time database in Node.js using Sequelize makes it easier to manage your SQL databases, especially when you need to interact with MySQL. By following these steps, you can efficiently synchronize your database, handle form data, and store it securely.
Sequelize, along with Express.js, provides a robust framework for connecting to a MySQL database in Node.js, making it an excellent choice for developers looking to work with SQL databases.
