CREATE TABLE Address (
  Id int PRIMARY KEY,
  Street string,
  City string,
  PostalCode int
);

CREATE TABLE Professor (
  Id int PRIMARY KEY,
  Name string,
  Sal double,
  addr int /* REFERENCES Address(Id) */
);

CREATE TABLE Student (
  Name string,
  GPA double,
  Yr int
);

CREATE TABLE PayRate (
  Rank int PRIMARY KEY,
  HrRate double
);

CREATE TABLE WorksOn (
  Name string,
  Proj string,
  Hrs int,
  ProjRank int /* REFERENCES PayRate(Rank) */
);