CREATE TABLE users (
	user_id		INT(8) NOT NULL AUTO_INCREMENT,
	user_name	VARCHAR(30) NOT NULL,
	user_pass	VARCHAR(255) NOT NULL,
	user_date	DATETIME NOT NULL,
	UNIQUE INDEX user_name_unique (user_name),
	PRIMARY KEY (user_id)
) ENGINE = InnoDB;

CREATE TABLE categories (
	cat_id			INT(8) NOT NULL AUTO_INCREMENT,
	cat_name		VARCHAR(255) NOT NULL,
	cat_description	VARCHAR(255) NOT NULL,
	UNIQUE INDEX cat_name_unique (cat_name),
	PRIMARY KEY (cat_id)
) ENGINE = InnoDB;

CREATE TABLE topics (
	topic_id		INT(8) NOT NULL AUTO_INCREMENT,
	topic_subject	VARCHAR(255) NOT NULL,
	topic_date		DATETIME NOT NULL,
	topic_cat		INT(8) NOT NULL,
	topic_author	INT(8) NOT NULL,
	PRIMARY KEY (topic_id)
) ENGINE = InnoDB;

CREATE TABLE posts (
post_id INT(8) NOT NULL AUTO_INCREMENT,
post_content TEXT NOT NULL,
post_date DATETIME NOT NULL,
post_topic INT(8) NOT NULL,
post_author INT(8) NOT NULL,
PRIMARY KEY (post_id)
) ENGINE = InnoDB;

ALTER TABLE topics ADD FOREIGN KEY(topic_cat) REFERENCES categories(cat_id) ON DELETE CASCADE ON UPDATE CASCADE;
ALTER TABLE topics ADD FOREIGN KEY(topic_author) REFERENCES users(user_id) ON DELETE RESTRICT ON UPDATE CASCADE;
ALTER TABLE posts ADD FOREIGN KEY(post_topic) REFERENCES topics(topic_id) ON DELETE CASCADE ON UPDATE CASCADE;
ALTER TABLE posts ADD FOREIGN KEY(post_author) REFERENCES users(user_id) ON DELETE RESTRICT ON UPDATE CASCADE;