CREATE TABLE umami.website_event_join ( session_id UUID, visit_id UUID, created_at DateTime('UTC') ) engine = MergeTree ORDER BY (session_id, created_at) SETTINGS index_granularity = 8192; INSERT INTO umami.website_event_join SELECT DISTINCT s.session_id, generateUUIDv4() visit_id, s.created_at FROM (SELECT DISTINCT session_id, date_trunc('hour', created_at) created_at FROM website_event) s; -- create new table CREATE TABLE umami.website_event_new ( website_id UUID, session_id UUID, visit_id UUID, event_id UUID, hostname LowCardinality(String), browser LowCardinality(String), os LowCardinality(String), device LowCardinality(String), screen LowCardinality(String), language LowCardinality(String), country LowCardinality(String), subdivision1 LowCardinality(String), subdivision2 LowCardinality(String), city String, url_path String, url_query String, referrer_path String, referrer_query String, referrer_domain String, page_title String, event_type UInt32, event_name String, created_at DateTime('UTC'), job_id UUID ) engine = MergeTree ORDER BY (website_id, session_id, created_at) SETTINGS index_granularity = 8192; INSERT INTO umami.website_event_new SELECT we.website_id, we.session_id, j.visit_id, we.event_id, we.hostname, we.browser, we.os, we.device, we.screen, we.language, we.country, we.subdivision1, we.subdivision2, we.city, we.url_path, we.url_query, we.referrer_path, we.referrer_query, we.referrer_domain, we.page_title, we.event_type, we.event_name, we.created_at, we.job_id FROM umami.website_event we JOIN umami.website_event_join j ON we.session_id = j.session_id and date_trunc('hour', we.created_at) = j.created_at WHERE we.created_at > '2023-03-31'; RENAME TABLE umami.website_event TO umami.website_event_old; RENAME TABLE umami.website_event_new TO umami.website_event; /* DROP TABLE umami.website_event_old DROP TABLE umami.website_event_join */