Table schema:
CREATE TABLE Customers (Address_ID VARCHAR); CREATE TABLE Addresses (City_Town VARCHAR, Address_ID VARCHAR); CREATE TABLE Performers (Address_ID VARCHAR)

Question: Show all cities where at least one customer lives in but no performer lives in.
SQL: SELECT T1.City_Town FROM Addresses AS T1 JOIN Customers AS T2 ON T1.Address_ID = T2.Address_ID EXCEPT SELECT T1.City_Town FROM Addresses AS T1 JOIN Performers AS T2 ON T1.Address_ID = T2.Address_ID