CREATE TABLE CUSTOMER (SupportRepId VARCHAR, PostalCode VARCHAR)
CREATE TABLE EMPLOYEE (City VARCHAR, EmployeeId VARCHAR)

What city does the employee who helps the customer with postal code 70174 live in?
SELECT T2.City FROM CUSTOMER AS T1 JOIN EMPLOYEE AS T2 ON T1.SupportRepId = T2.EmployeeId WHERE T1.PostalCode = "70174"
SELECT "T2"."City" FROM "CUSTOMER" AS "T1" JOIN "EMPLOYEE" AS "T2" ON "T1"."SupportRepId" = "T2"."EmployeeId" WHERE "70174" = "T1"."PostalCode"