first draft of schema

dumps/students/s_03/schema.sql

@@ -0,0 +1,91 @@
+DROP TABLE IF EXISTS clients CASCADE;
+DROP TABLE IF EXISTS employees CASCADE;
+DROP TABLE IF EXISTS services CASCADE;
+DROP TABLE IF EXISTS promotions CASCADE;
+DROP TABLE IF EXISTS vacations CASCADE;
+DROP TABLE IF EXISTS shifts CASCADE;
+DROP TABLE IF EXISTS employees_shifts CASCADE;
+DROP TABLE IF EXISTS promotions_services CASCADE;
+DROP TABLE IF EXISTS skills CASCADE;
+DROP TABLE IF EXISTS services_skills CASCADE;
+DROP TABLE IF EXISTS employees_skills CASCADE;
+
+CREATE TABLE clients(
+  id                  SERIAL PRIMARY KEY,
+  first_name          VARCHAR(50) NOT NULL,
+  last_name           VARCHAR(50) NOT NULL,
+  date_of_birth       DATE,  /* client have the right to refuse disclosing her DOB */
+  phone_number        VARCHAR(12),
+  email               VARCHAR(50),
+  personal_discount   SMALLINT CONSTRAINT discount CHECK (personal_discount >= 0 AND personal_discount <= 100)
+);
+
+CREATE TABLE services(
+  id                  SERIAL PRIMARY KEY,
+  title               VARCHAR(30) NOT NULL,
+  description         TEXT NOT NULL,
+  price               MONEY NOT NULL
+);
+
+CREATE TABLE promotions(
+  id                  SERIAL PRIMARY KEY,
+  title               VARCHAR(30) NOT NULL,
+  description         TEXT NOT NULL,
+  start_date          DATE NOT NULL,
+  end_date            DATE  /* some promotional offers may last an indefinitely long time */
+);
+
+
+CREATE TABLE promotions_services(
+  id                  SERIAL PRIMARY KEY,
+  promotion_id        INT REFERENCES promotions (id),
+  service_id          INT REFERENCES services (id),
+  promo_discount      SMALLINT CONSTRAINT discount CHECK (promo_discount >= 0 AND promo_discount <= 100)
+);
+
+CREATE TABLE employees(
+  id                  SERIAL PRIMARY KEY,
+  first_name          VARCHAR(50) NOT NULL,
+  last_name           VARCHAR(50) NOT NULL,
+  date_of_birth       DATE NOT NULL,
+  phone_number        VARCHAR(12),
+  hourly_rate         MONEY NOT NULL
+);
+
+CREATE TABLE skills(
+  id                  SERIAL PRIMARY KEY,
+  title               VARCHAR(30) NOT NULL,
+  description         TEXT NOT NULL
+);
+
+CREATE TABLE services_skills(
+  id                  SERIAL PRIMARY KEY,
+  service_id          INT REFERENCES services (id),
+  skill_id            INT REFERENCES skills (id)
+);
+
+CREATE TABLE employees_skills(
+  id                  SERIAL PRIMARY KEY,
+  employee_id          INT REFERENCES employees (id),
+  skill_id            INT REFERENCES skills (id),
+  skill_level         SMALLINT CONSTRAINT skill_level CHECK (skill_level >= 0 AND skill_level <= 10)
+);
+
+CREATE TABLE vacations(
+  id                  SERIAL PRIMARY KEY,
+  employee_id         INT REFERENCES employees (id),
+  start_date          DATE NOT NULL,
+  end_date            DATE  /* if an amployee is sick */
+);
+
+CREATE TABLE shifts(
+  id                  SERIAL PRIMARY KEY,
+  start_datetime      DATE NOT NULL,
+  end_datetime        DATE NOT NULL
+);
+
+CREATE TABLE employees_shifts(
+  id                  SERIAL PRIMARY KEY,
+  employee_id         INT REFERENCES employees (id),
+  shift_id            INT REFERENCES shifts (id)
+);