PET-project 1st task completed

2026-02-16 13:16:37 +03:00
parent 87ba57befe
commit 0c961319b9
1 changed files with 35 additions and 0 deletions
@@ -200,3 +200,38 @@ VALUES
 (56, 14, 7, '2023-01-11 10:00:00'),
 (57, 14, 8, '2023-01-12 11:00:00'),
 (58, 14, 9, '2023-01-10 08:00:00');
 ---------------------------------------------------------
 -- 1 задание Активные пользователи
 create materialized view user_activity_summary AS
 with enroll_count as (
 					select u.id as user_id, u.name as user_name, 
 					COUNT(e.course_id) as enrollment_count
 					from users u
 					join enrollments e on u.id = e.user_id
 					group by u.id, u.name
 					),
 viewed_count as (
 				select ec.user_id, ec.user_name, enrollment_count,
 				COUNT(distinct lv.lesson_id) as viewed_lessons_count,
 				MIN(lv.viewed_at) as first_view,
 				MAX(lv.viewed_at) as last_view
 				from enroll_count ec
 				left join lesson_views lv on ec.user_id = lv.user_id
 				group by ec.user_id, ec.user_name, enrollment_count
 				),
 possible_lessons as (		
 					select u.id as user_id, COUNT(l.id) as poss_lessons 
 					from users u
 					left join enrollments e on u.id = e.user_id
 					left join lessons l on e.course_id = l.course_id 
 					group by u.id
 					)
 select vc.user_id, user_name, enrollment_count, viewed_lessons_count, first_view, last_view, 
 ROUND(100.0 * viewed_lessons_count / pl.poss_lessons, 2) as engagement_rate
 from viewed_count vc
 left join possible_lessons pl on vc.user_id = pl.user_id
 ;