mybatis添加数据返回主键

水深无声 2022-06-08 03:57 234阅读 0赞

**程序结构图：**

![Center][]

**表结构：**

![Center 1][]

**创表sql：**

<table> 
 <tbody> 
  <tr> 
   <td>Create Table</td> 
  </tr> 
  <tr> 
   <td><br> CREATE&nbsp;TABLE&nbsp;`users`&nbsp;(<br> &nbsp;&nbsp;`id`&nbsp;int(11)&nbsp;NOT&nbsp;NULL&nbsp;AUTO_INCREMENT,<br> &nbsp;&nbsp;`username`&nbsp;varchar(200)&nbsp;DEFAULT&nbsp;NULL,<br> &nbsp;&nbsp;`password`&nbsp;varchar(32)&nbsp;DEFAULT&nbsp;NULL,<br> &nbsp;&nbsp;`sex`&nbsp;char(1)&nbsp;DEFAULT&nbsp;NULL,<br> &nbsp;&nbsp;`birthday`&nbsp;date&nbsp;DEFAULT&nbsp;NULL,<br> &nbsp;&nbsp;PRIMARY&nbsp;KEY&nbsp;(`id`)<br> )&nbsp;ENGINE=InnoDB&nbsp;AUTO_INCREMENT=19&nbsp;DEFAULT&nbsp;CHARSET=utf8</td> 
  </tr> 
 </tbody> 
</table>

**User.xml**

<?xml version="1.0" encoding="UTF-8" ?>  
<!DOCTYPE mapper  
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"   
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">  
  
<mapper namespace="test">

<insert id="insertUser" parameterType="com.itheima.mybatis.po.User">  
  
<selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">  
SELECT LAST\_INSERT\_ID()  
</selectKey>  
INSERT INTO users(username,password,sex,birthday)   
           VALUES(\#\{username\},\#\{password\},\#\{sex\},\#\{birthday\})  
</insert>

</mapper>

**当然也需要在全局配置文件中加入User.xml**

<?xml version="1.0" encoding="UTF-8" ?>  
<!DOCTYPE configuration  
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"  
"http://mybatis.org/dtd/mybatis-3-config.dtd">  
<configuration>  
  
<environments default="development">  
<environment id="development">  
<transactionManager type="JDBC" />  
<dataSource type="POOLED">  
<property name="driver" value="com.mysql.jdbc.Driver" />  
<property name="url" value="jdbc:mysql://localhost:3306/mybatisdb?characterEncoding=utf-8" />  
<property name="username" value="root" />  
<property name="password" value="123" />  
</dataSource>  
</environment>  
</environments>  
  
  
<mappers>  
<mapper resource="sqlmap/User.xml"/>  
</mappers>  
</configuration>

**测试代码：**

@Test  
public void testInserUser() throws IOException\{  
// 加载配置文件  
String resource = "SqlMapConfig.xml";  
InputStream inputStream = Resources.getResourceAsStream(resource);  
// 通过配置文件获得SqlSessionFactory对象  
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);  
// 通过sqlSessionFactory对象获得sqlSession对象  
SqlSession sqlSession = sqlSessionFactory.openSession();  
// 执行插入操作  
// 定义一个要插入的对象  
User user = new User();  
user.setUsername("李四");  
user.setPassword("123");  
user.setBirthday(new Date());  
sqlSession.insert("test.insertUser",user);  
  
// 测试是否获得主键id  
int id = user.getId();  
System.out.println(id);  
  
// 提交事务  
sqlSession.commit();  
  
// 关闭资源  
sqlSession.close();  
\}

执行结果：

控制台打印：

![Center 2][]

数据库查看：

![Center 3][]

[Center]: /images/20220608/5884e8ce27f74680bad1c0652dda22c2.png
[Center 1]: /images/20220608/ef28f6e134044ffca97e1524350e9742.png
[Center 2]: /images/20220608/1d0aefb900d0491b81d52845fc119b9f.png
[Center 3]: /images/20220608/3e3abb03533c415fbef90c9b94419e25.png