How to Make a search function using Node Express and MYSQL

In this article, we will learn how to create a search function using Node with Express framework to search terms inside MYSQL tables.

Prerequisites:

• MySQL
• Node JS
• Express JS

We will discuss the following methods to search:

Approach to make search function:

We're making a web application using Express.js and connecting it to a MySQL database. When users visit the '/search' route and provide a search term as a parameter, the app looks for that term in the database. If there's an error, we log it and send a 500 error. If not, we send back the search results in JSON format. We're using Node.js with Express for all this.

Steps to Create a Express application:

Step 1: Initialize npm (node package manager) using the following command

npm init

Step 2: Install mysql2 package using the following npm install command.

 npm install mysql2

Step 3: Create a new JavaScript file with .js extension (Example: app.js ) and write the code.

Step 4: For testing, create a new database and sample records using the following SQL query. Run the query in the MySQL workspace.

Project Structure:

The updated dependencies in package.json file will look like:

"dependencies": {
    "express": "^4.18.2",
    "mysql2": "^3.6.5",
}

Step 5: Run the application using following command:

node app.js

Step 6: Navigate to 'http://localhost:3000/search' and pass search term in the query using '?term= <search term>' .

Example: http://localhost:3000/search?term=geeksforgeeks

Note:

Important Note:
Replace host, user, password and database with your actual values.
Example:
const db = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'root',
  database: 'mydatabase',
});

Approach 1: Searching term with partial match:

It performs a partial match on 'name' column using LIKE and % wildcard in SQL query. Search the term with partial match in 'name' column using the following query. The LIKE operator with search term surrounded by % allows for a partial match ( const searchValue = `%${searchTerm}%`; ).

Replace it with following SQL query:

const query = `
   SELECT * FROM items
   WHERE name LIKE ?
`;

Example: Below is the code example of Searching term with partial match:

const express = require('express');
const mysql = require('mysql2');

const app = express();
const port = 3000;

// MySQL connection
const db =
    mysql.createConnection({
        host: 'localhost',
        user: 'root',
        password: 'root',
        database: 'mydatabase',
    });

// Connect to MySQL
db.connect(err => {
    if (err) {
        console.error('Error connecting to MySQL:', err);
    } else {
        console.log('Connected to MySQL');
    }
});

// Search endpoint
app.get('/search', (req, res) => {
    const searchTerm = req.query.term;
    if (!searchTerm) {
        return res.status(400)
            .json(
                {
                    error: 'Search term is required'
                }
            );
    }

    const query = `
    SELECT * FROM items
    WHERE name LIKE ?
  `;

    // Use '%' to perform a partial match
    const searchValue = `%${searchTerm}%`;

    db.query(query, [searchValue, searchValue],
        (err, results) => {
            if (err) {
                console
                    .error('Error executing search query:', err);
                return res.status(500)
                    .json(
                        {
                            error: 'Internal server error'
                        });
            }

            res.json(results);
        });
});

// Start the server
app.listen(port, () => {
    console.log(`Server is running on 
        http://localhost:${port}`);
});