Environment Windows Android studio 4.0 Beta 1 Android docs https://developer.android.com/training/data-storage/room/relationships https://developer.android.com/reference/androidx/room/Junction Medium https://medium.com/androiddevelopers/database-relations-with-room-544ab95e4542 Android Dev Summit '19 https://www.youtube.com/watch?v=_aJsh6P00c0