pet gp postgre done

2025-12-09 20:02:19 +03:00
parent 53398bc3ad
commit 2f80be77ed
2 changed files with 323 additions and 0 deletions
@@ -0,0 +1,180 @@
+CREATE SCHEMA raw;    
+CREATE SCHEMA core;     
+CREATE SCHEMA dm;
+
+CREATE TABLE raw.users (
+    id INT,
+    name VARCHAR(255),
+    age INT,
+    email VARCHAR(255),
+    registration_date DATE
+);
+
+CREATE TABLE raw.courses (
+    id INT,
+    title VARCHAR(255),
+    category VARCHAR(255),
+    created_at DATE
+);
+
+CREATE TABLE raw.lessons (
+    id INT,
+    course_id INT,
+    title VARCHAR(255),
+    duration_min INT
+);
+
+CREATE TABLE raw.enrollments (
+    id INT,
+    user_id INT,
+    course_id INT,
+    enrolled_at DATE
+);
+
+CREATE TABLE raw.lesson_views (
+    id INT,
+    user_id INT,
+    lesson_id INT,
+    viewed_at TIMESTAMP
+);
+
+CREATE TABLE core.dim_user (
+    user_id INT PRIMARY KEY,
+    name TEXT,
+    age INT,
+    email TEXT,
+    registration_date DATE
+);
+
+CREATE TABLE core.dim_course (
+    course_id INT PRIMARY KEY,
+    title TEXT,
+    category TEXT
+);
+
+CREATE TABLE core.dim_lesson (
+    lesson_id INT PRIMARY KEY,
+    title TEXT,
+    duration_min INT,
+    course_id INT REFERENCES core.dim_course(course_id)
+);
+
+CREATE TABLE core.fact_lesson_views (
+    user_id INT REFERENCES core.dim_user(user_id),
+    lesson_id INT REFERENCES core.dim_lesson(lesson_id),
+    course_id INT REFERENCES core.dim_course(course_id),
+    viewed_at TIMESTAMP
+);
+
+CREATE TABLE core.enrollments (
+    user_id INT REFERENCES core.dim_user(user_id),
+    course_id INT REFERENCES core.dim_course(course_id),
+    enrolled_at TIMESTAMP
+);
+
+INSERT INTO core.dim_user (user_id, name, age, email, registration_date)
+SELECT DISTINCT 
+    id::INT,
+    name::TEXT,
+    age::INT,
+    email::TEXT,
+    registration_date::DATE
+FROM raw.users;
+
+INSERT INTO core.dim_course (course_id, title, category)
+SELECT DISTINCT 
+    id::INT,
+    title::TEXT,
+    category::TEXT
+FROM raw.courses;
+
+INSERT INTO core.dim_lesson (lesson_id, title, duration_min, course_id)
+SELECT DISTINCT 
+    id::INT,
+    title::TEXT,
+    duration_min::INT,
+    course_id::INT
+FROM raw.lessons;
+
+INSERT INTO core.fact_lesson_views (user_id, lesson_id, course_id, viewed_at)
+SELECT DISTINCT
+    rw.user_id::INT,
+    rw.lesson_id::INT,
+    l.course_id::INT,
+    rw.viewed_at::TIMESTAMP
+FROM raw.lesson_views rw
+JOIN raw.lessons l ON rw.lesson_id = l.id;
+
+
+INSERT INTO core.enrollments (user_id, course_id, enrolled_at)
+SELECT DISTINCT 
+    user_id::INT,
+    course_id::INT,
+    enrolled_at::DATE
+FROM raw.enrollments;
+
+UPDATE core.enrollments e
+SET enrolled_at = lv.viewed_at
+FROM raw.lesson_views lv 
+WHERE lv.user_id = e.user_id;
+
+ALTER TABLE core.enrollments 
+ALTER COLUMN enrolled_at TYPE TIMESTAMP;
+
+CREATE MATERIALIZED VIEW dm.dm_lesson_popularity_summary AS
+SELECT 
+    dl.lesson_id,
+    dl.title AS lesson_title,
+    dc.course_id,
+    dc.title AS course_title,
+    COUNT(flv.lesson_id) AS total_views,
+    COUNT(DISTINCT du.user_id) AS unique_users,
+    MIN(flv.viewed_at) AS first_view,
+    MAX(flv.viewed_at) AS last_view
+FROM core.dim_lesson dl
+JOIN core.dim_course dc ON dc.course_id = dl.course_id
+JOIN core.fact_lesson_views flv ON flv.lesson_id = dl.lesson_id
+JOIN core.dim_user du ON du.user_id = flv.user_id
+GROUP BY dl.lesson_id, dl.title, dc.course_id, dc.title
+ORDER BY dl.lesson_id;
+
+select  * from dm.dm_lesson_popularity_summary 
+order by lesson_id;
+
+CREATE MATERIALIZED VIEW dm.dm_inactive_users_summary AS
+SELECT 
+    du.user_id,
+    du.name AS user_name,
+    du.email,
+    du.age,
+    COUNT(e.course_id) AS enrollments_count,
+    du.registration_date
+FROM core.dim_user du
+LEFT JOIN core.enrollments e ON e.user_id = du.user_id
+LEFT JOIN core.fact_lesson_views flv ON flv.user_id = du.user_id
+WHERE flv.user_id IS NULL
+GROUP BY du.user_id, du.name, du.email, du.age, du.registration_date;
+
+
+CREATE MATERIALIZED VIEW dm.course_completion_rate AS
+SELECT 
+    du.user_id,
+    du.name AS user_name,
+    c.course_id,
+    c.title AS course_title,
+    COUNT(DISTINCT dl.lesson_id) AS lessons_in_course,
+    COUNT(DISTINCT flv.lesson_id) AS lessons_viewed,
+    ROUND(
+        COUNT(DISTINCT flv.lesson_id) * 1.0 / 
+        NULLIF(COUNT(DISTINCT dl.lesson_id), 0), 
+        2
+    ) AS completion_rate
+FROM core.dim_user du
+JOIN core.enrollments e ON du.user_id = e.user_id
+JOIN core.dim_course c ON e.course_id = c.course_id
+JOIN core.dim_lesson dl ON c.course_id = dl.course_id
+LEFT JOIN core.fact_lesson_views flv ON dl.lesson_id = flv.lesson_id 
+    AND flv.user_id = du.user_id
+GROUP BY du.user_id, du.name, c.course_id, c.title
+ORDER BY du.user_id, c.course_id;
+
@@ -0,0 +1,143 @@
+create table users(
+	id int primary key,
+	name varchar(255),
+	age int,
+	email varchar(255),
+	registration_date date 
+);
+
+insert into users(id, name, age, email, registration_date) values 
+(1, 'Alice', 25, 'alice@mail.com', '2023-01-10'),
+(2, 'Bob', 30, 'bob@gmail.com', '2023-02-05'),
+(3, 'Charlie', 22, 'charlie@mail.com', '2023-02-20'),
+(4, 'Diana', 28, 'diana@mail.com', '2023-03-01'),
+(5, 'Ethan', 35, 'ethan@gmail.com', '2023-03-10');
+
+create table courses(
+	id int primary key,
+	title varchar(255),
+	category varchar(255),
+	created_at date 
+);
+
+insert into courses(id, title, category, created_at) values
+(1,	'SQL для начинающих', 'data', '2023-01-01'),
+(2,	'Python для анализа данных', 'programming',	'2023-01-15'),
+(3,	'BI с нуля', 'business', '2023-03-01');
+
+create table lessons(
+	id int primary key,
+	course_id int,
+	title varchar(255),
+	duration_min int,
+	foreign key (course_id) references courses(id)
+);
+	
+insert into lessons(id, course_id, title, duration_min) values
+(1,	1,	'SELECT и FROM', 10),
+(2,	1,	'JOIN',	15),
+(3,	2,	'Pandas', 20),
+(4,	3,	'Основы BI', 12),
+(5,	3,	'Метрики и дашборды', 18);
+
+create table enrollments(
+	id int primary key,
+	user_id int,
+	course_id int,
+	enrolled_at date,
+	foreign key (user_id) references users(id),
+	foreign key (course_id) references courses(id)
+);
+
+insert into enrollments (id, user_id, course_id, enrolled_at) values
+(1,	1,	1,	'2023-01-15'),
+(2,	1,	2,	'2023-02-01'),
+(3,	2,	1,	'2023-01-20'),
+(4,	3,	2,	'2023-03-05'),
+(5,	4,	3,	'2023-04-01');
+
+create table lesson_views(
+	id int primary key,
+	user_id int,
+	lesson_id int,
+	viewed_at timestamp,
+	foreign key (user_id) references users(id),
+	foreign key (lesson_id) references lessons(id)
+);
+
+insert into lesson_views(id, user_id, lesson_id, viewed_at) values
+(1,	1,	1,	'2023-01-16 10:00:00'),
+(2,	1,	2,	'2023-01-16 10:15:00'),
+(3,	2,	1,	'2023-01-21 09:00:00'),
+(4,	3,	3,	'2023-03-06 12:00:00'),
+(5,	4,	4,	'2023-04-02 10:00:00'),
+(6,	4,	5,	'2023-04-03 10:00:00');
+
+
+create materialized view user_activity_summary as (
+with available_lessons as (
+	select 
+		e.user_id,
+		count(distinct l.id) as cnt_lesson
+	from lessons l
+	join enrollments e on e.course_id = l.course_id 
+	group by e.user_id
+)
+select 
+	u.id,
+	u.name,
+	count(distinct e.course_id) as enrrollment_count,
+	count(distinct lv.lesson_id) as viewed_lessons_count,
+	max(lv.viewed_at) as last_view,
+	min(lv.viewed_at) as first_view,
+	round(
+		count(distinct lv.lesson_id) * 100.0 / al.cnt_lesson
+	,2) || '%' as engagegement_rate
+from users u
+join enrollments e on u.id = e.user_id 
+join lesson_views lv on lv.user_id = u.id 
+join available_lessons al on al.user_id = u.id 
+group by u.id, u.name, al.cnt_lesson
+);
+
+create materialized view course_summary as(
+with view_cnt as (
+	select l.course_id,
+	count(lv.lesson_id) cnt
+	from lessons l
+	join lesson_views lv on l.id = lv.lesson_id
+	group by l.course_id	
+)
+select 
+    c.id as course_id,
+	c.title,
+	count(distinct e.user_id) unique_users,
+	count(distinct l.id) lessons_count,
+	vc.cnt total_views,
+	round(vc.cnt * 1.0 / count(distinct e.user_id), 2) as avg_views_per_user,
+	min(lv.viewed_at) as first_viewed_at,
+	max(lv.viewed_at) as last_viewed_at
+from
+	courses c
+	join lessons l on c.id = l.course_id
+	join enrollments e on e.course_id = c.id 
+	join view_cnt vc on vc.course_id = c.id 
+	join lesson_views lv on lv.lesson_id = l.id
+group by c.title, vc.cnt, c.id 
+order by course_id
+);
+
+create materialized view platform_summary as (
+select 
+	count(distinct u.id) as total_users,
+	count(distinct c.id) as total_courses,
+	count(distinct l.id) as total_lessons,
+	count(distinct lv.user_id) as users_with_views,
+	round(count(distinct l.id) * 1.0 / count(distinct c.id), 2) as avg_lessons_per_course,
+	count(lv.lesson_id) * 1.0 / count(distinct l.id)  as avg_lessons_per_lesson
+from users u
+left join lesson_views lv on lv.user_id = u.id
+left join lessons l on l.id = lv.lesson_id
+left join courses c on c.id = l.course_id
+);
+