added STEP4.1, STEP4.2, STEP5

2025-12-25 12:25:42 +03:00
parent 6b5ae71123
commit ebc2f07fc8
4 changed files with 75 additions and 1 deletions
@@ -0,0 +1,42 @@
+/*
+ - ВИТРИНА АНАЛИЗА ПОПУЛЯРНОСТИ КАЖДОГО УРОКА
+ - ВСЕ УЧАСТВУЮЩИЕ ИЗМЕРЕНИЯ DISTRIBUTED REPLICATED
+ - ИТОГОВОЕ ПРЕДСТВАЛЕНИЕ DISTRIBUTED BY (lesson_id, course_id)
+ */
+
+CREATE MATERIALIZED VIEW IF NOT EXISTS dm.lesson_popularity_summary AS
+-- EXPLAIN ANALYZE
+WITH t1 AS (
+SELECT 
+	lesson_id,
+	course_id,
+	COUNT(lesson_id) AS total_views,
+	COUNT(DISTINCT user_id) AS unique_users,
+	MIN(viewed_at)AS first_view,
+	MAX(viewed_at)AS last_view
+FROM core.fact_lesson_views
+GROUP BY lesson_id, course_id
+),
+t2 AS (
+SELECT 
+	l.lesson_id,
+	l.title AS lesson_title,
+	c.course_id,
+	c.title AS course_title
+FROM core.dim_course c 
+LEFT JOIN core.dim_lesson l USING(course_id)
+
+)
+SELECT 
+	t1.lesson_id,
+	t2.lesson_title,
+	t1.course_id,
+	t2.course_title,
+	t1.total_views,
+	t1.unique_users,
+	t1.first_view,
+	t1.last_view
+FROM t1
+LEFT JOIN t2 USING(lesson_id)
+
+DISTRIBUTED BY (lesson_id, course_id);