Table Constraints

-- Drill 14 — قيود الجدول CHECK و UNIQUE و FK — SQLite 3.x+
PRAGMA foreign_keys = ON;

CREATE TABLE customers (
  id INTEGER PRIMARY KEY,
  name TEXT NOT NULL
);

CREATE TABLE coupons (
  id INTEGER PRIMARY KEY,
  code TEXT NOT NULL UNIQUE,
  percent INTEGER NOT NULL CHECK (percent BETWEEN 1 AND 100),
  active INTEGER NOT NULL DEFAULT 1,
  customer_id INTEGER REFERENCES customers(id) ON DELETE SET NULL
);

INSERT INTO customers (id, name) VALUES (1, 'Sara');

INSERT INTO coupons (code, percent, customer_id)
VALUES ('WELCOME', 15, 1);

SELECT code, percent, active, customer_id
FROM coupons;