text: -- Feel free to modify this file to match your development goal.
  -- Here we only create 3 tables for demo purpose.
  
  CREATE TABLE Users (
      id INT NOT NULL PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
      email VARCHAR UNIQUE NOT NULL,
      password VARCHAR(255) NOT NULL,
      firstname VARCHAR(255) NOT NULL,
      lastname VARCHAR(255) NOT NULL,
      isseller BOOLEAN NOT NULL
  );
  
  CREATE TABLE Products (
      id INT NOT NULL  GENERATED BY DEFAULT AS IDENTITY,
      cid INT NOT NULL 
      name VARCHAR(255) UNIQUE NOT NULL,
      price DECIMAL(12,2) NOT NULL,
      available BOOLEAN DEFAULT TRUE,
      PRIMARY KEY (cid,name)
  );
  
  
  
  CREATE TABLE Purchases (
      id INT NOT NULL PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
      uid INT NOT NULL REFERENCES Users(id),
      pid INT NOT NULL REFERENCES Products(id),
      time_purchased timestamp without time zone NOT NULL DEFAULT (current_timestamp AT TIME ZONE 'UTC')
  );
  CREATE TABLE Inventory(
      id INT NOT NULL PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
      sid INT NOT NULL REFERENCES Users(id),
      pid INT NOT NULL REFERENCES Products(cid),
      name VARCHAR(255) NOT NULL REFERENCES Products(name),
      description varchar(MAX),
      quantity INT NOT NULL CHECK (quantity >= 0),
      price DECIMAL(12,2) NOT NULL, 
      release_date timestamp without time zone NOT NULL DEFAULT (current_timestamp AT TIME ZONE 'UTC')
  );
  