SQL Syntax error foreign key

Question

I've a problem, i try to connect 2 db table, and if I make the query for make a DB structure the answer is Syntax Error.

I paste the code here, somebody can help me ?

DROP TABLE IF EXISTS album;
CREATE TABLE `album` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `title` varchar(30) DEFAULT NULL,
  `description` varchar(200) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=armscii8;

DROP TABLE IF EXISTS picture;
CREATE TABLE `picture` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `id_album` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  FOREIGN KEY (`id_album`) REFERENCES album(id)
) ENGINE=InnoDB DEFAULT CHARSET=armscii8;

sorry for my bad english.

Answer 1

认为您的id_album必须具有unsigned bean，与album id相同

Answer 2

Just add Unsigned in Foreign key line as follows :

DROP TABLE IF EXISTS album;
CREATE TABLE `album` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `title` varchar(30) DEFAULT NULL,
  `description` varchar(200) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=armscii8;

DROP TABLE IF EXISTS picture;
CREATE TABLE `picture` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `id_album` int(11) unsigned DEFAULT NULL,
  PRIMARY KEY (`id`),
  FOREIGN KEY (`id_album`) REFERENCES album(id)
) ENGINE=InnoDB DEFAULT CHARSET=armscii8;