Can the database ID be specified on an existing redis component when defining cache or session?

Yii 2.0 General Discussions
1

A REDIS component can be defined like:

‘components’ => [
‘redis’ => [
‘class’ => ‘yii\redis\Connection’,
‘hostname’ => ‘localhost’,
‘port’ => 6379,
‘database’ => 0,
],
]

then, cache or session components can be defined using this redis component without having to re-define the connection - like:

‘components’ => [
// …
‘session’ => [
‘class’ => ‘yii\redis\Session’,
‘redis’ => ‘redis’
],
]

If I wish to partition Session to use database 1 and Cache to use database 2, how can I set this up in the previous example? I don’t seem to be able to just add ‘database’ => 1. Do I always have to set up a different redis connection for each component using a different database?

2 
'components' => [
    'redisCache' => [
        'class' => 'yii\redis\Connection',
        'hostname' => 'localhost',
        'port' => 6379,
        'database' => 0,
    ],
    'redisSession' => [
        'class' => 'yii\redis\Connection',
        'hostname' => 'localhost',
        'port' => 6380,
        'database' => 0,
    ],
    'session' => [
        'class' => 'yii\redis\Session',
        'redis' => 'redisSession'
    ],
    'cache' => [
        'class' => 'yii\redis\Cache',
        'redis' => 'redisCache'
    ],
]