Show me all the musicians who performed in the song "Flash".
select * from performance as t1 join band as t2 on t1.bandmate = t2.id join songs as t3 on t3.songid = t1.songid where t2.lastname = "Flash"
How many are there?
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"