nodejs install mysql globally

Node.js is an open source cross-platform JavaScript runtime environment for server-side JavaScript programming. In Node.js, we can use various modules and libraries to accomplish various tasks, including interacting with databases. MySQL is one of the most popular relational databases and is the default choice for many web applications. This article will explain how to install MySQL globally in Node.js and start using it.

Step One: Install MySQL

Before using MySQL, we need to install MySQL first. We can download the MySQL installation package from the MySQL official website. Just select the appropriate version and follow the instructions to install it.

Step 2: Install the MySQL dependency library of Node.js

Once MySQL is installed, we need to use npm to install the MySQL dependency library of Node.js. Install mysql globally on our machine using the following command:

npm install -g mysql

This will install the MySQL driver and related dependencies. We can now use the mysql library in Node.js applications to connect to MySQL databases.

Step Three: Connect to MySQL

Before we can access MySQL, we need to connect to MySQL. This can be done with the following code:

const mysql = require('mysql');
const con = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "password",
  database: "mydb"
});

This will establish a connection to the local MySQL server, using username "root" and password "password", and connect to the database named "mydb".

Step 4: Execute the query

To execute the query in the MySQL database, we can use the following code:

const mysql = require('mysql');
const con = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "password",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  con.query("SELECT * FROM customers", function (err, result, fields) {
    if (err) throw err;
    console.log(result);
  });
});

In this example, we query the name "customers ” of all the data in the table and print the results in the console.

Step 5: Close the connection

When we complete the interaction with MySQL, we need to close the connection to release resources. This can be done using the following code:

const mysql = require('mysql');
const con = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "password",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  con.query("SELECT * FROM customers", function (err, result, fields) {
    if (err) throw err;
    console.log(result);
    con.end();
  });
});

In this example, we use the "con.end()" method to close the connection after the query ends.

Summary

By installing MySQL and using Node.js’s MySQL dependency library, we can easily interact with MySQL. It is important to note that when interacting with the database, you must always write your code according to best practices to ensure the security and correctness of the database.

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