Mybatis分页

野性酷女 2023-06-05 13:56 10阅读 0赞

# Mybatis分页 #

思考：为什么要分页？\*\*

*  减少数据的处理量

## 1、使用Limit分页 ##

List<User> getUserByLimit(Map<String,Integer> map);

第一步写接口

List<User> getUserByLimit(Map<String,Integer> map);

第二部在Mapper.xml中写SQL

<select id="getUserByLimit" parameterType="map" resultMap="UserMap">
    select * from  mybatis.user limit #{startIndex},#{pageSize}
    </select>

第三部测试

@Test
    public void getUserByLimit(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
    
        HashMap<String, Integer> map = new HashMap<String, Integer>();
        map.put("startIndex",1);
        map.put("pageSize",2);
    
        List<User> userList = (List<User>) mapper.getUserByLimit(map);
        for (User user : userList) {
            System.out.println(user);
        }
    
        sqlSession.close();
    }

## 2、RowBounds分页 ##

不再使用SQL实现分页

1.  接口
    
        //分页2
        List<User> getUserByRowBounds();
2.  mapper.xml
    
        
        <select id="getUserByRowBounds" resultMap="UserMap">
            select * from  mybatis.user
        </select>
3.  测试
    
        @Test
        public void getUserByRowBounds(){ 
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        
        //RowBounds实现
        RowBounds rowBounds = new RowBounds(1, 2);
        
        //通过Java代码层面实现分页
        List<User> userList = sqlSession.selectList("com.kuang.dao.UserMapper.getUserByRowBounds",null,rowBounds);
        
            for (User user : userList) { 
            System.out.println(user);
            }
        
            sqlSession.close();
            }

### 3、分页插件 ###

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