一、简单的增删查改
1.添加
<insert id="insertUser">
insert into user values (null,"cc","123445",20);
</insert>
2.删除
<!-- int deleteUser();-->
<delete id="deleteUser">
delete from user where id=3;
</delete>
3.修改
<!-- void updateUser();-->
<update id="updateUser">
update user set username='aa' where id=4;
</update>
4.查询
查询功能的标签必须设置resultType或resultMap
- resultType:设置默认的映射关系
- resultmap:设置自定义的映射关系
<!-- User getUserById();-->
<select id="getUserById" resultType="com.mybatis.Bean.User">
select * from user where id = 3;
</select>