首先,这是我的主要引用表mysql转储
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-- Server version: 5.6.17
-- PHP Version: 5.5.12
SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO"; SET time_zone = "+00:00";
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */; /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */; /*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */; /*!40101 SET NAMES utf8 */;
--
-- Database: `j_inventory`
--
-- --------------------------------------------------------
--
-- Table structure for table `users`
--
CREATE TABLE IF NOT EXISTS `users` ( `user_id` int(10) unsigned NOT NULL AUTO_INCREMENT, `username` varchar(200) COLLATE utf8_unicode_ci NOT NULL, `password` varchar(500) COLLATE utf8_unicode_ci NOT NULL, `real_password` varchar(250) COLLATE utf8_unicode_ci NOT NULL, `role` varchar(50) COLLATE utf8_unicode_ci NOT NULL, `full_name` varchar(250) COLLATE utf8_unicode_ci NOT NULL, `remember_token` varchar(100) COLLATE utf8_unicode_ci DEFAULT NULL, `created_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00', `updated_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00', `status` varchar(100) COLLATE utf8_unicode_ci NOT NULL, PRIMARY KEY (`user_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=44 ;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */; /*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */; /*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
第二个表希望外键所在
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-- Server version: 5.6.17
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SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO"; SET time_zone = "+00:00";
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */; /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */; /*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */; /*!40101 SET NAMES utf8 */;
--
-- Database: `j_inventory`
--
-- --------------------------------------------------------
--
-- Table structure for table `user_details`
--
CREATE TABLE IF NOT EXISTS `user_details` ( `id` int(11) NOT NULL AUTO_INCREMENT, `phone` varchar(200) NOT NULL, `age` int(100) NOT NULL, `gender` varchar(50) NOT NULL, `address` varchar(250) NOT NULL, `course` varchar(250) NOT NULL, `college` varchar(200) NOT NULL, `year` int(11) NOT NULL, `user_id` int(100) NOT NULL, `updated_at` timestamp NOT NULL, `created_at` timestamp NOT NULL, PRIMARY KEY (`id`), KEY `user_id` (`user_id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=3 ;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */; /*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */; /*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
users_details中的外键(由于mysql错误“无法添加外键约束”而未设置)是'user_id',引用表是'users'表,其中外键的引用键是用户表上的 'user_id' 我试过了
ALTER TABLE user_details ADD FOREIGN KEY fk1(user_id) REFERENCES users(user_id) ON DELETE CASCADE ON UPDATE NO ACTION;
但不幸的是,它抛出了一个错误
Error SQL query:
ALTER TABLE
user_details
ADD CONSTRAINTfk1
FOREIGN KEY (user_id
) REFERENCESj_inventory
.users
(user_id
) ON DELETE CASCADE ON UPDATE NO ACTION; MySQL said: Documentation1215 - Cannot add foreign key constraint Documentation
有什么帮助、线索、想法、建议、建议吗?
最佳答案
您的用户 ID 在用户表中未签名。从您的用户表创建语句中的此字段中删除“未签名”并查看它是否有效。我认为您看到的是由于用户和 user_details 表中的 user_id 字段类型不匹配导致的错误
关于mysql - 无法添加外键约束,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/33748117/