Пет-проект Greenplum (полностью)

2026-01-23 00:12:06 +04:00
parent ac9a2e0906
commit 93b3777a42
3 changed files with 105 additions and 0 deletions
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 --Витрина dm.lesson_popularity_summary
 CREATE MATERIALIZED VIEW dm.lesson_popularity_summary as
 select 
 	l.lesson_id,
 	l.title as lesson_title,
 	c.course_id,
 	c.title as course_title,
 	COUNT(f.user_id) as total_views,
 	COUNT(DISTINCT f.user_id) as unique_users,
 	MIN(f.viewed_at) as first_view,
 	MAX(f.viewed_at) as last_view
 FROM core.fact_lesson_views f
 JOIN core.dim_lesson l
    ON f.lesson_id = l.lesson_id
 JOIN core.dim_course c
    ON l.course_id = c.course_id
 GROUP BY
    l.lesson_id,
    l.title,
    c.course_id,
    c.title
 order by lesson_id;
 select * from dm.lesson_popularity_summary;
 --Удалил лишний индекс
 DROP INDEX core.idx_fact_views_course_id;
 -- Все индексы для  CORE-таблиц
 SELECT 
    tablename,
    indexname,
    indexdef
 FROM pg_indexes 
 WHERE schemaname = 'core'
  AND tablename IN (
      'dim_course',
      'dim_date', 
      'dim_lesson',
      'dim_user',
      'enrollments',
      'fact_lesson_views'
  )
 ORDER by indexname, tablename;
 --Витрина dm.inactive_users_summary
 CREATE MATERIALIZED VIEW 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 du.user_id = e.user_id
 left join core.fact_lesson_views flv
 	on du.user_id = flv.user_id
 where flv.user_id is NULL
 group by
 	du.user_id,
 	du.name,
 	du.email,
 	du.age,
 	du.registration_date
 order by du.user_id;
 select * from dm.inactive_users_summary;
 --Витрина dm.course_completion_rate
 CREATE MATERIALIZED VIEW dm.course_completion_rate as
 select
 	du.user_id,
 	du.name as user_name,
 	dc.course_id,
 	dc.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)::numeric / NULLIF(COUNT(DISTINCT dl.lesson_id), 0), 2) AS completion_rate
 from core.enrollments e
 left join core.dim_user du
    on du.user_id = e.user_id
 left join core.dim_course dc
    on dc.course_id = e.course_id
 left join core.dim_lesson dl
    on dl.course_id = e.course_id
 left join core.fact_lesson_views flv
    on flv.user_id = e.user_id
   and flv.lesson_id = dl.lesson_id
 group by
    du.user_id,
 	du.name,
 	dc.course_id,
 	dc.title
 order by du.user_id;
 select * from dm.course_completion_rate order by user_id;
 --Этап 5. Проверка 
 SELECT * FROM dm.lesson_popularity_summary LIMIT 10;
 SELECT * FROM dm.inactive_users_summary LIMIT 10;
 SELECT * FROM dm.course_completion_rate LIMIT 10;
 --Все витрины отображаются корректно. Скрины: "название витрины".png