How to set up a database connection in CodeIgniter?

Setting up a database connection in CodeIgniter is a crucial step to enable your application to interact with a database. CodeIgniter simplifies this process, and I’ll guide you through the steps to establish a database connection:

1. Configuration File: CodeIgniter centralizes database configuration in the `application/config/database.php` file. Open this file, and you’ll find an array where you can specify your database connection details. You’ll need to provide information such as the database driver (e.g., MySQL, PostgreSQL, SQLite), hostname, username, password, and database name.

2. Load Database Library: To use the configured database settings, you need to load the database library in your controllers or models where you intend to interact with the database. You can do this using the `$this->load->database()` method within your controller’s constructor or any specific function. This step initializes the database connection.

3. Use Database Query Builder: CodeIgniter provides a powerful Query Builder class that simplifies database queries and enhances security. You can use it to construct SQL queries in a more readable and safe manner. For example, to fetch data from a table, you can use `$this->db->get(‘table_name’)`. CodeIgniter’s Query Builder also helps prevent SQL injection attacks.

4. Executing Queries: With the database library loaded and your database configuration set up, you can execute various database operations like inserting, updating, or deleting records. For instance, to insert data into a table, you can use `$this->db->insert(‘table_name’, $data)`.

5. Closing the Connection (Optional): CodeIgniter automatically closes the database connection when your script execution ends. However, if you want to explicitly close the connection, you can use `$this->db->close()`.

By following these steps, you can successfully set up a database connection in CodeIgniter and start leveraging its powerful database features to build dynamic web applications. Remember to secure your database credentials and follow best practices for database interactions to ensure the security and integrity of your application’s data.