MySQL深分页问题原理与三种解决方案

CREATE TABLE `player` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '主键',
  `player_id` varchar(256) NOT NULL COMMENT '运动员编号',
  `player_name` varchar(256) NOT NULL COMMENT '运动员名称',
  `height` int(11) NOT NULL COMMENT '身高',
  `weight` int(11) NOT NULL COMMENT '体重',
  `game_performance` text COMMENT '最近一场比赛表现',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8

@SpringBootTest(classes = TestApplication.class)
@RunWith(SpringJUnit4ClassRunner.class)
public class PlayerServiceTest {

    @Resource
    private PlayerRepository playerRepository;

    @Test
    public void initBigData() {
        for (int i = 0; i < 1000000; i++) {
            PlayerEntity entity = new PlayerEntity();
            entity.setPlayerId(UUID.randomUUID().toString());
            entity.setPlayerName("球员_" + System.currentTimeMillis());
            entity.setWeight(150);
            entity.setHeight(188);
            entity.setGamePerformance("{\"runDistance\":8900.0,\"passSuccess\":80.12,\"scoreNum\":3}");
            playerRepository.insert(entity);
        }
    }
}

select * from player limit 990000,5

select * from player a, (select id as tmpId from player limit 990000,5) b WHERE a.id = b.tmpId

explain select * from player a, (select id as tmpId from player limit 990000,5) b WHERE a.id = b.tmpId

select * from player where id > 990000 LIMIT 5

explain select * from player where id > 990000 LIMIT 5

<mapper namespace="com.test.java.front.test.mysql.deep.page.repository.PlayerRepository">

	<resultMap id="BaseResultMap" type="com.test.java.front.test.mysql.deep.page.entity.PlayerEntity">
		<id column="id" jdbcType="BIGINT" property="id" />
		<result column="player_id" jdbcType="VARCHAR" property="playerId" />
		<result column="player_name" jdbcType="VARCHAR" property="playerName" />
		<result column="height" jdbcType="INTEGER" property="height" />
		<result column="weight" jdbcType="INTEGER" property="weight" />
		<result column="game_performance" jdbcType="LONGVARCHAR" property="gamePerformance" />
	</resultMap>

	<sql id="Base_Column_List">
		id, player_id, player_name, height, weight, game_performance
	</sql>

	<sql id="conditions">
		<where>
			<if test="playerId != null">
				and player_id = #{playerId,jdbcType=VARCHAR}
			</if>
		</where>
	</sql>

	<sql id="pager">
		<if test="skip != null and limit != null">
			limit #{skip}, #{limit}
		</if>
	</sql>

	<!-- 查询条数 -->
	<select id="selectPageCount" parameterType="com.test.java.front.test.mysql.deep.page.param.biz.PlayerQueryParam" resultType="java.lang.Long">
		select count(*) from player
		<include refid="conditions" />
	</select>

	<!-- 分页方式1：普通分页存在深分页问题 -->
	<!-- select * from player limit 990000,5 -->
	<select id="selectPager1" parameterType="com.test.java.front.test.mysql.deep.page.param.biz.PlayerQueryParam" resultMap="BaseResultMap">
		select
		<include refid="Base_Column_List" />
		from player
		<include refid="conditions" />
		<include refid="pager" />
	</select>

	<!-- 分页方式2：覆盖索引优化深分页问题 -->
	<!-- select * from player a, (select id as tmpId from player limit 990000,5) b where a.id = b.tmpId -->
	<select id="selectPager2" parameterType="com.test.java.front.test.mysql.deep.page.param.biz.PlayerQueryParam" resultMap="BaseResultMap">
		select
		<include refid="Base_Column_List" />
		from player a,
		(
		select id as tmpId from player
		<include refid="conditions" />
		<include refid="pager" />
		) b
		where a.id = b.tmpId
	</select>

	<!-- 分页方式3：Id分页不支持跳页 -->
	<!-- select * from player where id > 990000 limit 5 -->
	<select id="selectPager3" parameterType="com.test.java.front.test.mysql.deep.page.param.biz.PlayerQueryIdParam" resultMap="BaseResultMap">
		select
		<include refid="Base_Column_List" />
		<include refid="conditions" />
		from player where id > #{startId} limit #{pageSize}
	</select>
</mapper>