text: CREATE DATABASE IF NOT EXISTS isuwitter;
  CREATE DATABASE IF NOT EXISTS isutomo;
  
  DROP TABLE IF EXISTS isuwitter.users;
  CREATE TABLE isuwitter.users (
      id BIGINT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,
      name VARCHAR(20) UNIQUE,
      salt VARCHAR(20),
      password VARCHAR(40)
  ) Engine=InnoDB DEFAULT CHARSET=utf8mb4;
  
  DROP TABLE IF EXISTS isuwitter.tweets;
  CREATE TABLE isuwitter.tweets (
      id BIGINT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,
      user_id BIGINT UNSIGNED,
      text TEXT,
      created_at DATETIME NOT NULL
  ) Engine=InnoDB DEFAULT CHARSET=utf8mb4;
  
  DROP TABLE IF EXISTS isutomo.friends;
  CREATE TABLE isutomo.friends (
      id BIGINT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,
      me VARCHAR(20) UNIQUE,
      friends TEXT
  ) Engine=InnoDB DEFAULT CHARSET=utf8mb4;
  