Instruments

idinstrumentName
1Guitar
2Piano

CountrySingers

idsingerNamecountryforeignKey
(→ Instruments.id)
1John DoeUSA1
2Jane SmithCanada2

BluegrassSingers

idsingerNamebluegrassStyleforeignKey
(→ Instruments.id)
1Tom Brown11
2Emily White02

Albums

idalbumTitlereleaseYear
1My First Album2000
2The Best of Me2010

AlbumTracks

idtrackNumbertitleduration
11Track 13:00
22Track 23:30

SingsOnAlbum

idsingerIdalbumId
(→ CountrySingers.id)(→ Albums.id)
111
221
332
442