CREATE TABLE band (id VARCHAR)
CREATE TABLE performance (bandmate VARCHAR, songid VARCHAR)
CREATE TABLE songs (songid VARCHAR, Title VARCHAR)

Hom many musicians performed in the song 'Flash'?
SELECT COUNT(*) FROM performance AS T1 JOIN band AS T2 ON T1.bandmate = T2.id JOIN songs AS T3 ON T3.songid = T1.songid WHERE T3.Title = "Flash"
SELECT COUNT(*) FROM "performance" AS "T1" JOIN "band" AS "T2" ON "T1"."bandmate" = "T2"."id" JOIN "songs" AS "T3" ON "Flash" = "T3"."Title" AND "T1"."songid" = "T3"."songid"