nodejs sqlite database installation

Node.js is a popular JavaScript runtime that provides many useful modules and libraries for building web applications. SQLite is an embedded relational database that can run on various operating systems, including Windows, Linux and Mac OS X. In Node.js, you can access the SQLite database by installing the sqlite3 module. This article will introduce how to install the sqlite3 module in Node.js.

1. Install Node.js

First of all, if you have not installed Node.js, you need to download and install it from the official website first. The specific operation process will not be repeated here.

2. Install SQLite

SQLite can be downloaded by visiting the official website to download the binary installation package, or it can be installed through the package manager. Depending on the operating system you are using, choose the appropriate installation method.

In Ubuntu system, you can install SQLite through the following command:

sudo apt-get install sqlite3 libsqlite3-dev

In Mac OS X system, you can use Homebrew to install SQLite:

brew install sqlite

In Windows system , you can download the precompiled version from the official website and follow the prompts to complete the installation.

3. Install the sqlite3 module

You can use npm to install the sqlite3 module. Use the following command to complete the installation:

npm install sqlite3 --save

This will install the sqlite3 module and add it to the package .json file in the dependencies list.

4. Use the sqlite3 module

After installing the sqlite3 module, you can use the module in Node.js to access the SQLite database. First you need to use the require() function to load the module into the script:

const sqlite3 = require('sqlite3').verbose();

Then, you can create a new sqlite3.Database object to connect to the SQLite database:

let db = new sqlite3.Database('./database.db');

here'./database .db' is the path to the SQLite database file. If the file does not exist, a new database file will be automatically created.

Next, you can use the db.run() method to execute the SQL statement:

db.run('CREATE TABLE users (id INT PRIMARY KEY, name TEXT, age INT)');

This will create a table named users, containing three columns: id, name, and age.

db.run('INSERT INTO users (id, name, age) VALUES (?, ?, ?)', [1, '张三', 20], function(err) {
  if (err) {
    console.log(err);
  }
  else {
    console.log('Inserted row with id', this.lastID);
  }
});

This will insert a row of data into the users table and output the id of the newly inserted row to the console.

db.all('SELECT * FROM users', function(err, rows) {
  if (err) {
    console.log(err);
  }
  else {
    console.log(rows);
  }
});

This will retrieve all rows from the users table and output the results to the console.

5. Summary

Through the above steps, we can successfully install the sqlite3 module in Node.js and connect to the SQLite database. This allows us to use SQL statements to manipulate data and perform other operations such as inserting new data, retrieving data, updating data, deleting data, etc. If you need to use a database in a Node.js application, a SQLite database is a simple, reliable and easy-to-use option.

The above is the detailed content of nodejs sqlite database installation. For more information, please follow other related articles on the PHP Chinese website!