在MySql中创建外键时出错

Question

我试图在两个表之间建立关系。我的表名是employees和salaries。我尝试了以下代码：

ALTER TABLE `salaries` 
ADD FOREIGN KEY (`eid`) 
REFERENCES `employees`(`id`) 
ON DELETE CASCADE 
ON UPDATE CASCADE;

但它显示了一个错误：

在eid上创建外键时出错(检查数据类型)

员工表结构：

+---------------------------------------+
| id           | int(11)      | primary |
|--------------+--------------+---------|
| name         | varchar(255) | unique  |
|--------------+--------------+---------|
| basic        | int(11)      |         |
|--------------+--------------+---------|
| ot_rate      | int(11)      |         |
|--------------+--------------+---------|
| joining_date | date         |         |
+---------------------------------------+

薪资表结构：

+---------------------------------------+
| id           | int(11)      | primary |
|--------------+--------------+---------|
| eid          | int(11)      | index   | <-- I want to create foreign key on this column with employees->id.
|--------------+--------------+---------|
| month        | varchar(255) |         |
|--------------+--------------+---------|
| date         | date         |         |
|--------------+--------------+---------|
| working_day  | int(11)      |         |
+--------------+--------------+---------+
| ot_hour      | int(11)      |         |
|--------------+--------------+---------|
| ot_amount    | int(11)      |         |
|--------------+--------------+---------|
| basic_amount | int(11)      |         |
|--------------+--------------+---------|
| tatal_salary | inf(11)      |         |
|--------------+--------------+---------|
| comment      | varchar(255) |         |
+---------------------------------------+

我尝试将eid的数据类型更改为varchar、tinyint、text等。所有这些都有相同的错误信息。

更新

使用后：

ALTER TABLE `salaries` 
ADD CONSTRAINT `salary` FOREIGN KEY (`eid`) 
REFERENCES `employees`(`id`) 
ON DELETE CASCADE 
ON UPDATE CASCADE;

我收到以下错误消息：

#1005 - Can't create table `zamzam`.`#sql-14b4_1a5` (errno: 150 "Foreign key constraint is incorrectly formed")

Answer 1

您是否使用表中的关系视图选项来创建外键对比。此链接将向您展示方法-http://www.binarytides.com/create-foreign-key-phpmyadmin/谢谢