help – foreign key, backjoint between 3 tables

hi guys,

i have table youtube_channel_playlist with 2 foreign keys to 2 other tables youtube_channel and youtube_playlist:

CONSTRAINT FK_channel_playlist__channel_id FOREIGN KEY (channel_id) REFERENCES youtube_channel (channel_id) ON UPDATE CASCADE,
CONSTRAINT FK_channel_playlist__playlist_id FOREIGN KEY (playlist_id) REFERENCES youtube_playlist (playlist_id) ON UPDATE CASCADE

when i try fetch all rows from youtube_channel_playlist with parameter $dbChannelId:
$rows = $this->database->table(‘youtube_playlist’)
->select(‘youtube_playlist.playlist_id’)
->select(‘youtube_playlist.yt_playlist_id’)
->select(‘youtube_playlist.yt_playlist_title’)
->where(‘:youtube_channel_playlist.youtube_channel.channel_id’, $dbChannelId)

I allways get such the error:
No reference found for $youtube_channel_playlist->youtube_channel

seems Nette understand “:youtube_channel_playlist” for relationship youtube_playlist to youtube_channel_playlist
but it does not understand next “.” in “youtube_channel_playlist.youtube_channel”

Please could you give an advance? Many thanks.