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;
+