CREATE TABLE invoices (id VARCHAR2, customer_id VARCHAR2)
CREATE TABLE tracks (name VARCHAR2, id VARCHAR2)
CREATE TABLE customers (id VARCHAR2, first_name VARCHAR2, last_name VARCHAR2)
CREATE TABLE invoice_lines (track_id VARCHAR2, invoice_id VARCHAR2)

List all tracks bought by customer Daan Peeters.
SELECT T1.name FROM tracks AS T1 JOIN invoice_lines AS T2 ON T1.id = T2.track_id JOIN invoices AS T3 ON T3.id = T2.invoice_id JOIN customers AS T4 ON T4.id = T3.customer_id WHERE T4.first_name = "Daan" AND T4.last_name = "Peeters"
SELECT "T1"."name" FROM "tracks" "T1" JOIN "invoice_lines" "T2" ON "T1"."id" = "T2"."track_id" JOIN "invoices" "T3" ON "T2"."invoice_id" = "T3"."id" JOIN "customers" "T4" ON "Daan" = "T4"."first_name" AND "Peeters" = "T4"."last_name" AND "T3"."customer_id" = "T4"."id"