mybatis分页查询(limit分页、RowBounds分页)

1、limit分页

(1)mapper接口:

 List<Student> getStudentByLim(HashMap<String, Integer> map);

(2)配置文件:

    <select id="getStudentByLim" resultType="pers.zhb.pojo.Student" parameterType="map">
        select * from student limit #{startIndex},#{pageSize}
    </select>

(3)测试:

    @Test
    public void getStudentByLimTest(){
        SqlSession sqlSession= MybatisUtils.getSqlSession();
        StudentMapper studentMapper=sqlSession.getMapper(StudentMapper.class);
        HashMap<String,Integer> map=new HashMap<String, Integer>();
        map.put("startIndex",0);
        map.put("pageSize",3);
        List<Student> students= studentMapper.getStudentByLim(map);
        for(Student student:students){
            System.out.println(student);
        }
    }
DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - Opening JDBC Connection
DEBUG [main] - Created connection 1728790703.
DEBUG [main] - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@670b40af]
DEBUG [main] - ==>  Preparing: select * from student limit ?,? 
DEBUG [main] - ==> Parameters: 0(Integer), 3(Integer)
DEBUG [main] - <==      Total: 3
Student{studentno='201811', sname='zhai', sex='男', birthday='1998-11-11', classno='80501', point='890', phone='1234567890', email='null', clas=null}
Student{studentno='201812', sname='zhai2', sex='男', birthday='1998-11-11', classno='80601', point='893', phone='19837372533', email='null', clas=null}
Student{studentno='201813', sname='zhai3', sex='男', birthday='1998-11-11', classno='80501', point='892', phone='19837372534', email='null', clas=null}

 

2、RowBounds分页(了解,不建议使用)

(1)接口:

List<Student> getStudentByRowBounds();

(2)配置文件:

    <select id="getStudentByRowBounds" resultType="pers.zhb.pojo.Student">
        select * from student
    </select>

(3)测试:

    @Test
    public void getStudentByRowBoundsTest(){
        SqlSession sqlSession= MybatisUtils.getSqlSession();
        RowBounds rowBounds=new RowBounds(1,2);
        List<Student> students=sqlSession.selectList
                ("pers.zhb.mapper.StudentMapper.getStudentByRowBounds",null,rowBounds);
        for (Student student : students) {
            System.out.println(student);
        }
        sqlSession.close();
    }
DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - Opening JDBC Connection
DEBUG [main] - Created connection 243745864.
DEBUG [main] - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@e874448]
DEBUG [main] - ==>  Preparing: select * from student 
DEBUG [main] - ==> Parameters: 
Student{studentno='201812', sname='zhai2', sex='男', birthday='1998-11-11', classno='80601', point='893', phone='19837372533', email='null', clas=null}
Student{studentno='201813', sname='zhai3', sex='男', birthday='1998-11-11', classno='80501', point='892', phone='19837372534', email='null', clas=null}
DEBUG [main] - Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@e874448]
DEBUG [main] - Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@e874448]
DEBUG [main] - Returned connection 243745864 to pool.

使用RowBounds实现的分页是基于代码的,二limit实现的分页是基于sql的

 

3、分页插件

官网含有该插件的文档,里面有详细的步骤

mybatis分页查询(limit分页、RowBounds分页)

 

 摘自:https://pagehelper.github.io/docs/

 

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