复杂SQL案例：用户听课情况查询

供参考：

select
h.course_id,
h.course_type,
i.course_title,
r.id res_id,
r.res_title,
h.user_id,
u.user_full_name user_name,u.phone,
round(d.living_duration/60,1) living_duration,round(d.record_duration/60,1) record_duration,
h.done_time,
(case when h.listen_status='1' then '已打卡' else '' end) listen_status,
d.create_time,d.update_time
from
(
-- 作业:用course_type关联course_id
select h.user_id,h.listen_status,h.score,h.done_time,c.course_id,c.course_type
from app_user.class_hwork_info h left join  app_user.class_info c on h.course_type=c.course_type
-- where h.user_id in(xxx) and h.course_type=xxx

) h
left join
(
-- 作业:用日期关联res_id
	select cx.course_id,cx.res_date done_time,res.res_id res_id
	from app_user.cxkt_res_date cx left join app_goods.course_info_res res on cx.course_info_res_id=res.id
	where cx.course_info_res_id>0
) c on h.course_id=c.course_id and h.done_time=c.done_time
left join
(
	select user_id,course_id,res_id,concat(res_id,'-',rel_id) all_res_id,living_duration,record_duration,create_time,update_time
	from  bi_data.user_study_rel_duration_
) d on h.course_id=d.course_id and h.user_id=d.user_id  and c.res_id=d.res_id
left join app_goods.course_info i on h.course_id=i.id
left join app_goods.course_res r on  c.res_id=r.id
left join app_user.user_info u on h.user_id=u.id