Kevin Bradwick

Using multiple database connections with Yii framework

There may be occasions where you will need to set up database connections to more than one database. This guide will show you the easy way to set up these resources.

In your main.php config file, you may already have a db component set up by default.

//.. main.php
'db'=>array(
	'connectionString' => 'mysql:host=localhost;dbname=testdrive',
	'emulatePrepare' => true,
	'username' => 'root',
	'password' => 'password',
	'charset' => 'utf8',
),

This will be enabled by default. Now, if you want to enable another connection component, simply add another CDbConnection component and give it a different name.

//.. main.php
'db'=>array(
	'connectionString' => 'mysql:host=localhost;dbname=testdrive',
	'emulatePrepare' => true,
	'username' => 'root',
	'password' => 'password',
	'charset' => 'utf8',
),
'db2'=>array(
        'class'  => 'CDbConnection',
	'connectionString' => 'mysql:host=localhost;dbname=database2',
	'emulatePrepare' => true,
	'username' => 'root',
	'password' => 'password',
	'charset' => 'utf8',
),

Now, in your models you can pass the connection instance using getDbConnection()

class DbTable extends CActiveRecord
{
     public static function model($className=__CLASS__)
    {
        return parent::model($className);
    }

    public function getDbConnection()
    {
        return Yii::app()->db2; // select the connection you want
    }
//.. etc

Using this technique you can have your model classes connect to numerous databases.

Enjoy