How to Connect to Multiple Databases in CodeIgnitor

CodeIgnitor framework provides a way for web developers to work with multiple databases. With just a few lines of code, you can easily connect to multiple databases and read different data types.

In application\config\database.php add these 2 database settings:

//1st database
$db['default'] = array(
	'dsn'	=> '',
	'hostname' => 'localhost',
	'username' => 'root',
	'password' => '',
	'database' => 'database1',
	'dbdriver' => 'mysqli',
	'dbprefix' => '',
	'pconnect' => FALSE,
	'db_debug' => (ENVIRONMENT !== 'production'),
	'cache_on' => FALSE,
	'cachedir' => '',
	'char_set' => 'utf8',
	'dbcollat' => 'utf8_general_ci',
	'swap_pre' => '',
	'encrypt' => FALSE,
	'compress' => FALSE,
	'stricton' => FALSE,
	'failover' => array(),
	'save_queries' => TRUE
);

2nd database

$db['default'] = array(
	'dsn'	=> '',
	'hostname' => '192.168.1.3',
	'username' => 'user2',
	'password' => 'passpass',
	'database' => 'database2',
	'dbdriver' => 'mysqli',
	'dbprefix' => '',
	'pconnect' => FALSE,
	'db_debug' => (ENVIRONMENT !== 'production'),
	'cache_on' => FALSE,
	'cachedir' => '',
	'char_set' => 'utf8',
	'dbcollat' => 'utf8_general_ci',
	'swap_pre' => '',
	'encrypt' => FALSE,
	'compress' => FALSE,
	'stricton' => FALSE,
	'failover' => array(),
	'save_queries' => TRUE
);

Query from 2nd database

$db = $this->load->database('seconddatabase', TRUE);
$query = $db->select('*')->from('article')->where($conditions)->order_by('id', 'DESC')->get();
$result = $query->result();