CREATE TABLE instruments (bandmateid VARCHAR2)
CREATE TABLE Band (id VARCHAR2, lastname VARCHAR2)

Find all the instruments ever used by the musician with last name 'Heilo'?
SELECT instrument FROM instruments AS T1 JOIN Band AS T2 ON T1.bandmateid = T2.id WHERE T2.lastname = "Heilo"
SELECT "instrument" FROM "instruments" "T1" JOIN "Band" "T2" ON "Heilo" = "T2"."lastname" AND "T1"."bandmateid" = "T2"."id"