витрина 'Воронка конверсии' для 'Пет-проект: Онлайн-курсы'

2026-03-22 15:08:45 +03:00
parent f7e6b757df
commit ce82641efb
1 changed files with 114 additions and 0 deletions
@@ -0,0 +1,114 @@
 WITH stage_courses AS (
 	-- registered
 	(SELECT
 		0 AS course_id,
 		1 AS stage_id,
 		'registered' AS stage_name,
 		count(DISTINCT u.id) AS users_count
 	FROM
 		users u)
 	UNION ALL
 	-- enrolled
 	(SELECT
 		e.course_id,
 		2 AS stage_id,
 		'enrolled' AS stage_name,
 		count(DISTINCT e.user_id) AS users_count
 	FROM
 		enrollments e
 	GROUP BY
 		e.course_id
 	ORDER BY
 		e.course_id)
 	UNION ALL	
 	-- started
 	(SELECT
 		l.course_id,
 		3 AS stage_id,
 		'started' AS stage_name,
 		count(DISTINCT lv.user_id) AS users_count
 	FROM
 		lessons l
 	JOIN
 		lesson_views lv ON l.id = lv.lesson_id
 	GROUP BY
 		l.course_id
 	ORDER BY
 		l.course_id)
 	UNION ALL
 	-- mid_progress
 	(WITH lessons_mid AS (
 		SELECT
 			l.course_id,
 			ceil(percentile_cont(0.5) WITHIN GROUP (ORDER BY l.id)) AS mid_in_lesson_id
 		FROM
 			lessons l
 		GROUP BY
 			l.course_id
 	)
 	SELECT
 		lm.course_id,
 		4 AS stage_id,
 		'mid_progress' AS stage_name,
 		count(lv.user_id) AS users_count
 	FROM
 		lessons_mid lm
 	LEFT JOIN
 		lesson_views lv ON lm.mid_in_lesson_id = lv.lesson_id
 	GROUP BY
 		lm.course_id, lm.mid_in_lesson_id
 	ORDER BY
 		lm.course_id)
 	UNION ALL
 	-- completed
 	(WITH courses_lessons_id AS (
 		SELECT
 			l.course_id,
 			l.id AS lesson_id
 		FROM
 			lessons l
 		GROUP BY
 			l.course_id, l.id
 	),
 	lessons_numbers AS (
 		SELECT
 			cli.course_id,
 			cli.lesson_id,
 			ROW_NUMBER() OVER(PARTITION BY cli.course_id ORDER BY cli.lesson_id DESC) AS lesson_number
 		FROM
 			courses_lessons_id cli
 	)
 	SELECT
 		ln.course_id,
 		5 AS stage_id,
 		'completed' AS stage_name,
 		count(lv.user_id) AS users_count
 	FROM
 		lessons_numbers ln
 	LEFT JOIN
 		lesson_views lv ON ln.lesson_id = lv.lesson_id
 	WHERE
 		ln.lesson_number = 1
 	GROUP BY
 		ln.course_id, ln.lesson_id
 	ORDER BY
 		ln.course_id)
 )
 SELECT
 	sc.course_id,
 	c.title AS course_title,
 	sc.stage_id,
 	sc.stage_name,
 	sc.users_count,
 	CASE
 		WHEN lag(sc.users_count) OVER (PARTITION BY sc.course_id ORDER BY sc.stage_id) IS NULL THEN 'first stage'
 		WHEN lag(sc.users_count) OVER (PARTITION BY sc.course_id ORDER BY sc.stage_id) = 0 THEN 0::text || '%'
 		WHEN lag(sc.users_count) OVER (PARTITION BY sc.course_id ORDER BY sc.stage_id) IS NOT NULL THEN round((sc.users_count / lag(sc.users_count) OVER (PARTITION BY sc.course_id ORDER BY sc.stage_id)::NUMERIC) * 100, 0)::text || '%'
 	END AS conversion_from_previous,
 	round((sc.users_count / FIRST_VALUE(sc.users_count) OVER (ORDER BY sc.stage_id)::NUMERIC) * 100, 0)::text || '%' AS conversion_from_start
 FROM
 	courses c
 RIGHT JOIN
 	stage_courses sc ON c.id = sc.course_id
 ORDER BY
 	sc.course_id