CREATE TABLE instruments (songid NUMBER, bandmateid NUMBER, instrument CLOB)
CREATE TABLE vocals (songid NUMBER, bandmate NUMBER, type CLOB)
CREATE TABLE tracklists (albumid NUMBER, position NUMBER, songid NUMBER)
CREATE TABLE albums (aid NUMBER, title CLOB, year NUMBER, label CLOB, type CLOB)
CREATE TABLE band (id NUMBER, firstname CLOB, lastname CLOB)
CREATE TABLE songs (songid NUMBER, title CLOB)
CREATE TABLE performance (songid NUMBER, bandmate NUMBER, stageposition CLOB)

How many songs have vocals of type lead?
SELECT COUNT(DISTINCT title) FROM vocals AS T1 JOIN songs AS T2 ON T1.songid = T2.songid WHERE type = "lead"
SELECT COUNT(DISTINCT "title") FROM "vocals" "T1" JOIN "songs" "T2" ON "T1"."songid" = "T2"."songid" WHERE "lead" = "type"