text: CREATE TABLE IF NOT EXISTS categories (
      id VARCHAR(64) NOT NULL PRIMARY KEY,
      uri VARCHAR(20) NOT NULL UNIQUE,
      title VARCHAR(20) NOT NULL
  );
  
  CREATE TABLE IF NOT EXISTS products (
      id VARCHAR(64) NOT NULL PRIMARY KEY,
      title VARCHAR(20) NOT NULL,
      description VARCHAR(50) NOT NULL DEFAULT(''),
      price DECIMAL(10,2)
  );
  
  CREATE TABLE IF NOT EXISTS products_in_categories (
      product_id VARCHAR(64) NOT NULL,
      category_id VARCHAR(64) NOT NULL,
      PRIMARY KEY (product_id, category_id)
  );
  