Mybatis数据基本操作

Posted 2022-02-12 fcitx

<insert id="doCreate" parameterType="News"><!--添加数据-->
        INSERT INTO news(title,content) VALUES (#title,#content) ;
        <selectKey keyColumn="nid" keyProperty="nid" order="AFTER" resultType="java.lang.Long">
            SELECT LAST_INSERT_ID()
        </selectKey>
    </insert>
    <update id="doEdit" parameterType="News"> <!--更新数据-->
            UPDATE  news SET title=#title,content=#content WHERE nid=#nid
        </update>
    <delete id="doRemove" parameterType="java.lang.Long"><!--删除数据-->
            DELETE  FROM news WHERE nid=#xiaoyu
        </delete>

查询数据（添加到News.xml）

  <select id="findById" parameterType="java.lang.Long" resultType="News"><查询数据>
        SELECT nid,title,content FROM news WHERE nid=#wodenid ;
    </select>
    <select id="findAll" resultType="News">
        SELECT nid,title,content FROM news ;
    </select>
    <select id="findAllTitle" resultType="News">
        SELECT nid,title FROM news ;
    </select>
    <select id="findSplit" resultType="News" parameterType="java.util.Map"> <分页查询>
        SELECT nid,title,content FROM news WHERE $column LIKE #keyword LIMIT #start,#lineSize ;
    </select>
    <select id="getAllCount" resultType="java.lang.Long">
        SELECT COUNT(*) FROM news ;
    </select>

数据更新测试

 1     @Test
 2     public void testDelete() throws Exception    //删除
 3         System.out.println("数据删除：" + MyBatisSessionFactory.getSession()
 4                 .update("com.lion.mapper.NewsNS.doRemove", 9L));
 5         MyBatisSessionFactory.getSession().commit();
 6         MyBatisSessionFactory.close();
 7     
 8     @Test
 9     public void testEdit() throws Exception               //修改
10         News vo = new News();
11         vo.setTitle("人生最舒服的日子？");
12         vo.setContent("你是个屌丝，梦里成为富翁");
13         vo.setNid(9L); // 修改数据时需要设置准确的编号
14         System.out.println("数据修改：" + MyBatisSessionFactory.getSession().update("com.lion.mapper.NewsNS.doEdit", vo));
15         MyBatisSessionFactory.getSession().commit();
16         MyBatisSessionFactory.close();
17         MyBatisSessionFactory.getSession().commit();
18         MyBatisSessionFactory.close();
19     
20     @Test
21     public void testSplit() throws Exception     //分页查询
22         Map<String,Object> splitParams = new HashMap<String,Object>() ; // 保存分页相关参数
23         splitParams.put("column", "title");
24         splitParams.put("keyword", "%%");
25         splitParams.put("start", 5); // (currentPage - 1) * lineSize
26         splitParams.put("lineSize", 5);
27         List<News> all = MyBatisSessionFactory.getSession().selectList("com.lion.mapper.NewsNS.findSplit",splitParams);
28         Long count = MyBatisSessionFactory.getSession().selectOne("com.lion.mapper.NewsNS.getAllCount",splitParams);
29         System.out.println("【分页数据】" + all);
30         System.out.println("【数据行统计】" + count);
31         MyBatisSessionFactory.close();
32