SQLite Databases

SQLite is a lightweight and widely used Relational Database Management System (RDBMS) that allows you to easily manage and store data across various platforms. It is a serverless, self-contained, and transactional SQL databases that doesn't need a separate server process to run.

Syntax

In SQLite, you can create databases and tables with the following syntax:

-- Create a new database
CREATE DATABASE database_name;

-- Use an existing database
USE database_name;

-- Create a new table
CREATE TABLE table_name (
    column1 data_type,
    column2 data_type,
    ...
);

Example

Suppose we want to create a database for managing employee records, we can create a table called employees to store employee details such as name, email, phone, and department.

-- Create a new database
CREATE DATABASE employee_management;

-- Use the new database
USE employee_management;

-- Create a new table
CREATE TABLE employees (
    id INTEGER PRIMARY KEY,
    name TEXT NOT NULL,
    phone TEXT,
    email TEXT UNIQUE NOT NULL,
    department TEXT
);

Output

We can verify that the employees table is created by running the following SQL statement:

SELECT name FROM sqlite_master WHERE type='table' AND name='employees';

The output of the SQL statement would be:

name
-----
employees

Explanation

In the example above, we create a database called employee_management using the CREATE DATABASE statement and then use that database for creating a new table called employees using the CREATE TABLE statement.

The employees table has five columns:

• id: an auto-incrementing integer column that serves as the primary key
• name: a required text column for the employee's name
• phone: an optional text column for the employee's phone number
• email: a required unique text column for the employee's email
• department: an optional text column for the employee's department

Use

SQLite is a popular choice for building mobile, desktop, and web applications due to its simple and lightweight nature. SQLite is also useful for testing and prototyping database-driven applications as well without having to set up a heavyweight RDBMS.

Important Points

• SQLite is self-contained and serverless, making it ideal for small and standalone applications.
• SQLite supports standard SQL syntax and a wide range of common data types for creating tables.
• SQLite does not support concurrent write transactions and larger data sets which can lead to performance issues.

Summary

In this tutorial, we learned about SQLite databases and how to create and use them for storing and managing data across various platforms. We saw examples of creating a database and a table for storing employee records. SQLite is a self-contained and serverless RDBMS that can be used for building lightweight applications and testing database-driven applications.