Mybatis分页

Mybatis分页

为什么分页？

• 减少数据的处理量

使用使用Limit分页

核心sql语句：

<select id="getUserLimit" resultType="User" parameterType="map">
    select *from mybatis.user limit ${startIndex},${pageSize};
</select>

1. 接口

   //使用limit实现分页
   List<User> getUserLimit(Map<String,Integer> map);

2. Mapper.xml

   <select id="getUserLimit" resultType="User" parameterType="map">
       select *from mybatis.user limit ${startIndex},${pageSize};
   </select>

3. 测试

    @Test
       public void testgetUserLimit(){
           SqlSession sqlSession = MybatisUtils.getSqlSession();
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           Map<String,Integer> map = new HashMap<>();
           map.put("startIndex",0);
           map.put("pageSize",2);
   ​
   ​
           List<User> users = mapper.getUserLimit(map);
           for (User user:users){
   ​
               System.out.println(user);
           }
           sqlSession.close();
       }

RowBounds分页（老方法）

1. 接口

   //使用RowBounds分页
   List<User> getUserByRowBounds();

2. mapper.xml

   <select id="getUserByRowBounds" resultType="User">
       select * from user;
   </select>

3. 测试

   @Test
   public void testgerUserByRowBounds(){
   ​
       RowBounds rowBounds = new RowBounds(1,2);
       SqlSession sqlSession = MybatisUtils.getSqlSession();
       List<User> list = sqlSession.selectList("com.aishimin.dao.UserMapper.getUserByRowBounds", null, rowBounds);
   ​
       for(User user:list){
           System.out.println(user);
       }
   ​
       sqlSession.close();
   }

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