CREATE TABLE vocals (songid VARCHAR2)
CREATE TABLE songs (songid VARCHAR2)

How many songs have a shared vocal?
SELECT COUNT(DISTINCT title) FROM vocals AS T1 JOIN songs AS T2 ON T1.songid = T2.songid WHERE TYPE = "shared"
SELECT COUNT(DISTINCT "title") FROM "vocals" "T1" JOIN "songs" "T2" ON "T1"."songid" = "T2"."songid" WHERE "TYPE" = "shared"