1 计算视频完播率

2,对应sql 代码与答案

create database test002;
use test002;
DROP TABLE IF EXISTS tb_user_video_log, tb_video_info;
CREATE TABLE tb_user_video_log (
    id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
    uid INT NOT NULL COMMENT '用户ID',
    video_id INT NOT NULL COMMENT '视频ID',
    start_time datetime COMMENT '开始观看时间',
    end_time datetime COMMENT '结束观看时间',
    if_follow TINYINT COMMENT '是否关注',
    if_like TINYINT COMMENT '是否点赞',
    if_retweet TINYINT COMMENT '是否转发',
    comment_id INT COMMENT '评论ID'
) CHARACTER SET utf8 COLLATE utf8_bin;


CREATE TABLE tb_video_info (
    id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
    video_id INT UNIQUE NOT NULL COMMENT '视频ID',
    author INT NOT NULL COMMENT '创作者ID',
    tag VARCHAR(16) NOT NULL COMMENT '类别标签',
    duration INT NOT NULL COMMENT '视频时长(秒数)',
    release_time datetime NOT NULL COMMENT '发布时间'
)CHARACTER SET utf8 COLLATE utf8_bin;

INSERT INTO tb_user_video_log(uid, video_id, start_time, end_time, if_follow, if_like, if_retweet, comment_id) VALUES
  (101, 2001, '2021-10-01 10:00:00', '2021-10-01 10:00:30', 0, 1, 1, null),
  (102, 2001, '2021-10-01 10:00:00', '2021-10-01 10:00:24', 0, 0, 1, null),
  (103, 2001, '2021-10-01 11:00:00', '2021-10-01 11:00:34', 0, 1, 0, 1732526),
  (101, 2002, '2021-09-01 10:00:00', '2021-09-01 10:00:42', 1, 0, 1, null),
  (102, 2002, '2021-10-01 11:00:00', '2021-10-01 11:00:30', 1, 0, 1, null);

INSERT INTO tb_video_info(video_id, author, tag, duration, release_time) VALUES
  (2001, 901, '影视', 30, '2021-01-01 7:00:00'),
  (2002, 901, '美食', 60, '2021-01-01 7:00:00'),
  (2003, 902, '旅游', 90, '2021-01-01 7:00:00');
  

# 1，计算视频对应观看次数,观看时长,视频时长,完播次数
select vlog.video_id ,uid, count(vlog.video_id)  观看次数 ,
TIMESTAMPDIFF(second,start_time,end_time) 观看时长,
duration 视频时长,
sum(TIMESTAMPDIFF(second,start_time,end_time) >= duration) 完播次数
from tb_user_video_log as vlog 
left join (select video_id,duration from tb_video_info) t1
on vlog.video_id=t1.video_id
group by video_id;

# 计算视频完播率（完播次数/观看次数）
select t2.video_id,完播次数/观看次数 完播率 from
(
select vlog.video_id ,uid, count(vlog.video_id)  观看次数 ,
TIMESTAMPDIFF(second,start_time,end_time) 观看时长,
duration 视频时长,
sum(TIMESTAMPDIFF(second,start_time,end_time) >= duration) 完播次数
from tb_user_video_log as vlog 
left join (select video_id,duration from tb_video_info) t1
on vlog.video_id=t1.video_id
group by video_id) t2
group by video_id;