Select
  BoxSet.ArtistSort,
  BoxSet.Title,
  BoxSet.Released,
  BoxSet.AlbumCount,
  Album1.BoxSetIndex,
  Album1.ArtistSort As ArtistSort1,
  Album1.Released As Released1,
  Album1.Title As Title1,
  Album1.PlayingTime,
  (Select
    Sum(Album2.PlayingTime) As Sum_PlayingTime
  From
    Album Album2
  Where
    Album2.BoxSetID = Album1.BoxSetID And Album2.BoxSetIndex > 1
  Group By
    Album2.BoxSetID) As TotalPlayingTime
From
  BoxSet Inner Join
  Album Album1 On BoxSet.BoxSetID = Album1.BoxSetID
Order By
  BoxSet.ArtistSort,
  BoxSet.Title,
  Album1.BoxSetIndex
