mastodon/db/views/follow_recommendations_v02.sql
Claire d9ae3db8d5
Improve performance of follow recommendation scheduler (#16159)
Express follow_recommendations in terms of account_summaries rather than
accounts, integrate filters that are unconditionally used, and materialize
the resulting view.

This should result in the bulk of the computation being performed only once
instead of **once per recommendation language**.
2021-05-05 22:04:52 +02:00

34 lines
1.5 KiB
SQL

SELECT
account_id,
sum(rank) AS rank,
array_agg(reason) AS reason
FROM (
SELECT
account_summaries.account_id AS account_id,
count(follows.id) / (1.0 + count(follows.id)) AS rank,
'most_followed' AS reason
FROM follows
INNER JOIN account_summaries ON account_summaries.account_id = follows.target_account_id
INNER JOIN users ON users.account_id = follows.account_id
LEFT OUTER JOIN follow_recommendation_suppressions ON follow_recommendation_suppressions.account_id = follows.target_account_id
WHERE users.current_sign_in_at >= (now() - interval '30 days')
AND account_summaries.sensitive = 'f'
AND follow_recommendation_suppressions.id IS NULL
GROUP BY account_summaries.account_id
HAVING count(follows.id) >= 5
UNION ALL
SELECT account_summaries.account_id AS account_id,
sum(reblogs_count + favourites_count) / (1.0 + sum(reblogs_count + favourites_count)) AS rank,
'most_interactions' AS reason
FROM status_stats
INNER JOIN statuses ON statuses.id = status_stats.status_id
INNER JOIN account_summaries ON account_summaries.account_id = statuses.account_id
LEFT OUTER JOIN follow_recommendation_suppressions ON follow_recommendation_suppressions.account_id = statuses.account_id
WHERE statuses.id >= ((date_part('epoch', now() - interval '30 days') * 1000)::bigint << 16)
AND account_summaries.sensitive = 'f'
AND follow_recommendation_suppressions.id IS NULL
GROUP BY account_summaries.account_id
HAVING sum(reblogs_count + favourites_count) >= 5
) t0
GROUP BY account_id
ORDER BY rank DESC