Mybatis简单的增删改查

INSERT

<!--    插入-->
    <insert id="insertUser" parameterType="edu.ccit.cn.domain.User">
        insert into t_user (username,password)values(#{username},#{password})
    </insert>
    <!--通过select查询来生成主键
            [selectKey标签]：通过select查询来生成主键
            [keyProperty]：指定存放生成主键的属性
            [resultType]：生成主键所对应的Java类型
            [order]：指定该查询主键SQL语句的执行顺序，相对于insert语句
            [last_insert_id]：MySQL的函数，要配合insert语句一起使用

            如果设计数据库为主键自增 则不需要设置selectKey
-->
    <insert id="insertUser_autoid" parameterType="edu.ccit.cn.domain.User">
        <selectKey keyProperty="id" resultType="int" order="AFTER">
            SELECT LAST_INSERT_ID()
        </selectKey>
        INSERT INTO t_user (username,password)values (#{username},#{password})
    </insert>
    <!--生成uuid作为主键-->
    <insert id="insertUser_uuid" parameterType="edu.ccit.cn.domain.User">
        <selectKey keyProperty="id" resultType="int" order="AFTER">
            SELECT uuid()
        </selectKey>
        INSERT INTO t_user (username,password)values (#{username},#{password})
    </insert>

DELETE

<!--    删除-->
    <delete id="deleteUserById" parameterType="int">
        delete from t_user where id=#{id}
    </delete>

UPDATE

<!--    更新-->
    <update id="updateUserById" parameterType="edu.ccit.cn.domain.User">
        update t_user set username=#{username},password=#{password} where id=#{id}
    </update>

SELECT

<select id="findUserById" parameterType="int" resultType="edu.ccit.cn.domain.User">
        SELECT * FROM t_user WHERE id = #{id}
    </select>
<!--    模糊查询-->
    <select id="findUserByName" parameterType="String" resultType="edu.ccit.cn.domain.User">
        select * from t_user where username like '%${value}%'
    </select>

测试

import edu.ccit.cn.domain.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;

/**
 * @program: mybites01
 * @description
 * @author: LIANG
 * @create: 2021-05-28 19:14
 **/
public class Test_01 {
    @Test
    public void test1() throws IOException {
        //读取配置文件
        InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
        //创建sqlSessionFactory会话工厂
        SqlSessionFactory ssf = new SqlSessionFactoryBuilder().build(resourceAsStream);
        //创建SqlSession
        SqlSession session = ssf.openSession();
        //调用SqlSession操作数据库的方法
        User user = (User)session.selectOne("findUserById", 1);
        //插入数据
        session.insert("insertUser",new User("孙少平","tianxiaoxia"));
        //更新数据
        User updateUser = new User();
        updateUser.setId(1);
        updateUser.setUsername("张三");
        updateUser.setPassword("55");
        session.update("updateUserById",updateUser);
        //删除数据
        session.delete("deleteUserById",8);
        //主键自增更新数据
        session.insert("insertUser_autoid",new User("孙少安","hexiulian"));
        session.commit();
        session.close();
    }
}