CREATE TABLE `definitions` (
`id_definition` int(10) UNSIGNED auto_increment,
`id_user` int(10) UNSIGNED,
`title` VARCHAR(50),
`description` VARCHAR(500),
`led` TIMESTAMP NOT NULL ON UPDATE CURRENT_TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (`id_definition`),
UNIQUE KEY `uni_def_title` (`title`));

ALTER TABLE definitions ADD INDEX(`id_user`);
ALTER TABLE definitions ADD FOREIGN KEY (`id_user`) REFERENCES users(`id_user`);