1-2：投資メモアプリのデータベースとテーブルを作る

CREATE TABLE jpmarket_tbl(
	market_id TINYINT NOT NULL PRIMARY KEY,
	market CHAR(10) UNIQUE
);

CREATE TABLE jpstock_tbl(
	code_id SMALLINT NOT NULL PRIMARY KEY,
	stockname CHAR(128),
	market_id TINYINT
);

CREATE TABLE memo_tbl(
	memo_id INT ZEROFILL NOT NULL PRIMARY KEY AUTO_INCREMENT,
	code_id SMALLINT NOT NULL,
	user_id INT NOT NULL,
	memo TEXT(255),
	created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
	updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

CREATE TABLE user_tbl(
	user_id INT ZEROFILL NOT NULL PRIMARY KEY AUTO_INCREMENT,
	username CHAR(128) NOT NULL,
	email CHAR(128) NOT NULL UNIQUE,
	password CHAR(128) NOT NULL,
	created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
	updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);