From ebc2f07fc8caaba89392b93e016ae9a99268451e Mon Sep 17 00:00:00 2001
From: SERGEY_KONEV <skonev>
Date: Thu, 25 Dec 2025 12:25:42 +0300
Subject: [PATCH] added STEP4.1, STEP4.2, STEP5

---
 .../STEP4.1_dm.lesson_popularity_summary.sql  | 42 +++++++++++++++++++
 .../STEP4.2_dm.inactive_users_summary.sql     | 28 +++++++++++++
 .../STEP4.3_dm.course_completion_rate.sql     |  3 +-
 skonev/greenplum/STEP5_checking.sql           |  3 ++
 4 files changed, 75 insertions(+), 1 deletion(-)
 create mode 100644 skonev/greenplum/STEP4.1_dm.lesson_popularity_summary.sql
 create mode 100644 skonev/greenplum/STEP4.2_dm.inactive_users_summary.sql
 create mode 100644 skonev/greenplum/STEP5_checking.sql

diff --git a/skonev/greenplum/STEP4.1_dm.lesson_popularity_summary.sql b/skonev/greenplum/STEP4.1_dm.lesson_popularity_summary.sql
new file mode 100644
index 0000000..ed4479e
--- /dev/null
+++ b/skonev/greenplum/STEP4.1_dm.lesson_popularity_summary.sql
@@ -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);
\ No newline at end of file
diff --git a/skonev/greenplum/STEP4.2_dm.inactive_users_summary.sql b/skonev/greenplum/STEP4.2_dm.inactive_users_summary.sql
new file mode 100644
index 0000000..6ad6475
--- /dev/null
+++ b/skonev/greenplum/STEP4.2_dm.inactive_users_summary.sql
@@ -0,0 +1,28 @@
+/*
+ - ВИТРИНА АНАЛИЗА НЕАКТИВНЫХ ПОЛЬЗОВАТЕЛЕЙ
+ - ВСЕ УЧАСТВУЮЩИЕ ТАБЛИЦЫ DISTRIBUTED BY (user_id)
+ - ИТОГОВОЕ ПРЕДСТВАЛЕНИЕ ТАК ЖЕ DISTRIBUTED BY (user_id)
+ */
+
+
+CREATE MATERIALIZED VIEW IF NOT EXISTS dm.inactive_users_summary AS
+-- EXPLAIN ANALYZE
+WITH t1 AS (
+SELECT 
+	user_id,
+	count(DISTINCT course_id) AS enrollments_count
+FROM core.enrollments
+GROUP BY user_id
+)
+SELECT
+	u.user_id,
+	u.name AS user_name,
+	u.email,
+	u.age,
+	coalesce(t1.enrollments_count, 0),
+	u.registration_date
+FROM core.dim_user u
+LEFT JOIN t1  USING (user_id)
+WHERE u.user_id NOT IN (SELECT user_id FROM core.fact_lesson_views)
+
+DISTRIBUTED BY (user_id);
\ No newline at end of file
diff --git a/skonev/greenplum/STEP4.3_dm.course_completion_rate.sql b/skonev/greenplum/STEP4.3_dm.course_completion_rate.sql
index 75793df..0d2c4de 100644
--- a/skonev/greenplum/STEP4.3_dm.course_completion_rate.sql
+++ b/skonev/greenplum/STEP4.3_dm.course_completion_rate.sql
@@ -1,9 +1,10 @@
 /* 
 - ВИТРИНА ДЛЯ АНАЛИЗА КОНВЕРСИИ ПРОХОЖДЕНИЯ КУРСА ПОЛЬЗОВАТЕЛЯМИ
+- CORE.DIM_USER И CORE.FACT_LESSON_VIEWS DISTRIBUTED BY (user_id)
 - ИТОГОВОЕ РАСПРЕДЕЛЕНИЕ ПО (user_id, course_id)
 */
 
-CREATE MATERIALIZED VIEW dm.course_completion_rate AS
+CREATE MATERIALIZED VIEW IF NOT EXISTS dm.course_completion_rate AS
 WITH t1 AS (
 SELECT
 	e.user_id,
diff --git a/skonev/greenplum/STEP5_checking.sql b/skonev/greenplum/STEP5_checking.sql
new file mode 100644
index 0000000..106fa4a
--- /dev/null
+++ b/skonev/greenplum/STEP5_checking.sql
@@ -0,0 +1,3 @@
+SELECT * FROM dm.lesson_popularity_summary LIMIT 10;
+SELECT * FROM dm.inactive_users_summary LIMIT 10;
+SELECT * FROM dm.course_completion_rate LIMIT 10;
\ No newline at end of file