phpmyadmin的mysql外键(phpmyadmin mysql foreign key)

phpmyadmin的mysql外键(phpmyadmin mysql foreign key)

phpmyadmin版本：4.1.14

数据库引擎：InnoDB

索引已经设定：

ALTER TABLE `tbl_name` ADD INDEX( `user_id`);

我的查询：

ALTER TABLE `tbl_name` ADD FOREIGN KEY (`user_id`) REFERENCES `<db_name>`.`user`(`id`) ON DELETE RESTRICT ON UPDATE RESTRICT;

但我仍然有错误：

#1215 - Impossible d'ajouter des contraintes d'index externe

在mysql文档中这个错误：

Erreur: 1215 SQLSTATE: HY000 (ER_CANNOT_ADD_FOREIGN)

什么是错的，为解决这个问题我必须做些什么？ 也许我在phpmyadmin设置中忘记了一些东西？

phpmyadmin version: 4.1.14

db engine: InnoDB

index already set:

ALTER TABLE `tbl_name` ADD INDEX( `user_id`);

My query:

ALTER TABLE `tbl_name` ADD FOREIGN KEY (`user_id`) REFERENCES `<db_name>`.`user`(`id`) ON DELETE RESTRICT ON UPDATE RESTRICT;

but im still got error:

#1215 - Impossible d'ajouter des contraintes d'index externe

In mysql documentation this error:

Erreur: 1215 SQLSTATE: HY000 (ER_CANNOT_ADD_FOREIGN)

whats wrong and what i must do for solve this? Maybe i forgot something in phpmyadmin settings?

最满意答案

问题解决了，即时添加UNSIGNED到索引列（for user_id）

`user_id` INT UNSIGNED NOT NULL ,

我认为，有关系的领域必须具有相同的属性

Problem solved, im add UNSIGNED to indexed column (for user_id )

`user_id` INT UNSIGNED NOT NULL ,

I think, fields with relations must have same properties