s := relation{tuple{s# "S1",sname "Smith",status 20, city "London"}, tuple{s# "S2",sname "Jones",status 10,city "Paris"}, tuple{s# "S3",sname "Blake",status 30,city "Paris"}, tuple{s# "S4",sname "Clark",status 20,city "London"}, tuple{s# "S5",sname "Adams",status 30,city "Athens"}}
p := relation{tuple{p# "P1",PNAME "Nut",COLOR "Red",WEIGHT 12,city "London"}, tuple{p# "P2",PNAME "Bolt",COLOR "Green",WEIGHT 17,city "Paris"}, tuple{p# "P3",PNAME "Screw",COLOR "Blue",WEIGHT 17,city "Oslo"}, tuple{p# "P4",PNAME "Screw",COLOR "Red",WEIGHT 14,city "London"}, tuple{p# "P5",PNAME "Cam",COLOR "Blue",WEIGHT 12,city "Paris"}, tuple{p# "P6", PNAME "Cog", COLOR "Red",WEIGHT 19,city "London"}}
sp := relation{tuple{s# "S1",p# "P1",qty 300}, tuple{s# "S1",p# "P2",qty 200}, tuple{s# "S1",p# "P3",qty 400}, tuple{s# "S1",p# "P4",qty 200}, tuple{s# "S1",p# "P5",qty 100}, tuple{s# "S1",p# "P6",qty 100}, tuple{s# "S2",p# "P1",qty 300}, tuple{s# "S2",p# "P2",qty 400}, tuple{s# "S3",p# "P2",qty 200}, tuple{s# "S4",p# "P4",qty 300}, tuple{s# "S4",p# "P5",qty 400}}
foreign key sp2s sp{s#} in s{s#}
foreign key sp2p sp{p#} in p{p#}