CREATE TABLE person (
  uid INTEGER PRIMARY KEY,
  name TEXT,
  address TEXT
);

CREATE TABLE product (
  pid INTEGER PRIMARY KEY,
  name TEXT,
  address TEXT
);

CREATE TABLE company (
    cid INTEGER PRIMARY KEY,
    name TEXT,
    ceo TEXT,
    address TEXT
);

CREATE TABLE makes (
    uid INT REFERENCES product,
    cid INT REFERENCES company
);

DROP TABLE IF EXISTS makes;
CREATE TABLE makes (
    uid INT REFERENCES product,
    cid INT REFERENCES company,
    quantity Int
);

DROP TABLE IF EXISTS makes;
CREATE TABLE makes (
  pid int UNIQUE REFERENCES product,
  cid int UNIQUE REFERENCES company
);
  
DROP TABLE IF EXISTS makes;
CREATE TABLE makes (
  pid INTEGER PRIMARY KEY REFERENCES product,
  cid INT REFERENCES company
);

DROP TABLE IF EXISTS product;
CREATE TABLE product (
    pid INTEGER PRIMARY KEY,
    cid int REFERENCES company,
    name TEXT,
    address TEXT
);

DROP TABLE IF EXISTS product;
CREATE TABLE product (
    pid INTEGER PRIMARY KEY,
    cid int REFERENCES company NOT NULL,
    name TEXT,
    address TEXT);

DROP TABLE IF EXISTS product;
CREATE TABLE product (
    pid INTEGER PRIMARY KEY,
    name TEXT,
    address TEXT
);

DROP TABLE IF EXISTS makes;
CREATE TABLE makes (
    uid INT REFERENCES product,
    cid INT REFERENCES company
);

DROP TABLE IF EXISTS toy;
DROP TABLE IF EXISTS candy;
DROP TABLE IF EXISTS makes;
DROP TABLE IF EXISTS product;

CREATE TABLE product (
  pid INTEGER PRIMARY KEY,
  name TEXT,
  price REAL
);

CREATE TABLE toy (
  pid INTEGER PRIMARY KEY REFERENCES product,
  age INT
);

CREATE TABLE candy (
  pid INTEGER PRIMARY KEY REFERENCES product,
  is_chocolate INT
);


DROP TABLE IF EXISTS team;
DROP TABLE IF EXISTS university;

CREATE TABLE university (
  uname TEXT PRIMARY KEY,
  size INT
);

CREATE TABLE team (
  uname TEXT REFERENCES university,
  tname TEXT,
  sport TEXT,
  PRIMARY KEY (uname, tname)
);


CREATE ASSERTION myAssert CHECK
    (NOT EXISTS (
        SELECT makes.pid
          FROM makes
      GROUP BY Make.pid
        HAVING COUNT(*) > 20)
     );