From ace9b8b292636e5e4491e6ea694d4c0a9ad7c9a7 Mon Sep 17 00:00:00 2001
From: Alex <xarlama@bk.ru>
Date: Thu, 26 Feb 2026 15:17:39 +0300
Subject: [PATCH] Task 2 fixed

---
 aharlamcev/PET-project_task2 | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 aharlamcev/PET-project_task2

diff --git a/aharlamcev/PET-project_task2 b/aharlamcev/PET-project_task2
new file mode 100644
index 0000000..0de3482
--- /dev/null
+++ b/aharlamcev/PET-project_task2
@@ -0,0 +1,26 @@
+CREATE MATERIALIZED VIEW platform_summary AS
+with users_counts as (
+					select 
+					COUNT(distinct u.id) as total_users,
+					COUNT(distinct lv.user_id) as users_with_views
+					from users u
+					left join lesson_views lv on lv.user_id = u.id
+					),
+courses_lessons_count as (
+					select COUNT(distinct c.id) as total_courses,
+					COUNT(distinct l.id) as total_lessons
+					from courses c
+					left join lessons l on l.course_id = c.id
+					),
+views_count as (
+				select COUNT(distinct lv.lesson_id) as lessons_with_views,
+				COUNT(distinct lv.id) as total_views
+				from lesson_views lv
+				)
+select uc.total_users, clc.total_courses, clc.total_lessons, uc.users_with_views,
+ROUND(1.00 * clc.total_lessons / nullif(clc.total_courses, 0), 2) as avg_lessons_per_course,
+ROUND(1.00 * vc.total_views / nullif(clc.total_lessons, 0), 2) as avg_views_per_lesson
+from users_counts uc
+cross join courses_lessons_count clc
+cross join views_count vc
+;
\ No newline at end of file