users {
	id int unsigned primary,
	username text,
	password text,
	cash int unsigned
}

artists {
	id int unsigned primary,
	name text
}

genres {
	id int unsigned primary,
	name text
}

records {
	id int unsigned primary,
	artist_id int unsigned foreign(artists.id) cascade cascade,
	genre_id int unsigned foreign(genres.id) cascade cascade,
	title text,
	price int unsigned,
	cover text
}

user_carts {
	user_id int unsigned foreign(users.id) cascade cascade,
	record_id int unsigned foreign(records.id) cascade cascade
}

user_history {
	user_id int unsigned foreign(users.id) cascade cascade,
	record_id int unsigned foreign(records.id) cascade cascade,
	purchase_date datetime
}