SERGEY_KONEV
43 lines
969 B
SQL
43 lines
969 B
SQL
/*
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- ВИТРИНА АНАЛИЗА ПОПУЛЯРНОСТИ КАЖДОГО УРОКА
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- ВСЕ УЧАСТВУЮЩИЕ ИЗМЕРЕНИЯ DISTRIBUTED REPLICATED
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- ИТОГОВОЕ ПРЕДСТВАЛЕНИЕ DISTRIBUTED BY (lesson_id, course_id)
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*/
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CREATE MATERIALIZED VIEW IF NOT EXISTS dm.lesson_popularity_summary AS
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-- EXPLAIN ANALYZE
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DISTRIBUTED BY (lesson_id, course_id)
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WITH t1 AS (
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SELECT
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lesson_id,
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course_id,
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COUNT(*) AS total_views,
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COUNT(DISTINCT user_id) AS unique_users,
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MIN(viewed_at)AS first_view,
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MAX(viewed_at)AS last_view
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FROM core.fact_lesson_views
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GROUP BY lesson_id, course_id
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),
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t2 AS (
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SELECT
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l.lesson_id,
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l.title AS lesson_title,
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c.course_id,
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c.title AS course_title
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FROM core.dim_course c
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LEFT JOIN core.dim_lesson l USING(course_id)
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)
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SELECT
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t1.lesson_id,
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t2.lesson_title,
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t1.course_id,
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t2.course_title,
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t1.total_views,
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t1.unique_users,
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t1.first_view,
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t1.last_view
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FROM t1
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LEFT JOIN t2 USING(lesson_id, course_id);
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