DB.exec(<<~SQL, args)
INSERT INTO topic_hot_scores (
topic_id,
score,
recent_likes,
recent_posters,
created_at,
updated_at
)
SELECT
topics.id,
0.0,
0,
0,
:now,
:now
FROM topics
LEFT OUTER JOIN topic_hot_scores ON topic_hot_scores.topic_id = topics.id
WHERE topic_hot_scores.topic_id IS NULL
AND topics.deleted_at IS NULL
AND topics.archetype <> :private_message
AND topics.created_at <= :now
ORDER BY
CASE WHEN topics.pinned_at IS NOT NULL THEN 0 ELSE 1 END ASC,
topics.bumped_at desc
LIMIT :max
SQL
# update recent counts for batch
DB.exec(<<~SQL, args)
UPDATE topic_hot_scores thsOrig
SET
recent_likes = COALESCE(new_values.likes_count, 0),
recent_posters = COALESCE(new_values.unique_participants, 0),
recent_first_bumped_at = COALESCE(new_values.first_bumped_at, ths.recent_first_bumped_at)
FROM
topic_hot_scores ths
LEFT OUTER JOIN
(
SELECT
t.id AS topic_id,
COUNT(DISTINCT p.user_id) AS unique_participants,
(
SELECT COUNT(distinct pa.user_id)
FROM post_actions pa
JOIN posts p2 ON p2.id = pa.post_id
WHERE p2.topic_id = t.id
AND p2.post_type = :regular
AND p2.deleted_at IS NULL
AND p2.user_deleted = false
AND pa.post_action_type_id = 2 -- action_type for 'like'
AND pa.created_at >= :recent_cutoff
AND pa.deleted_at IS NULL
) AS likes_count,
MIN(p.created_at) AS first_bumped_at
FROM
topics t
JOIN
posts p ON t.id = p.topic_id
WHERE
p.created_at >= :recent_cutoff
AND t.archetype <> 'private_message'
AND t.deleted_at IS NULL
AND p.deleted_at IS NULL
AND p.user_deleted = false
AND t.created_at <= :now
AND t.bumped_at >= :recent_cutoff
AND p.created_at < :now
AND p.created_at >= :recent_cutoff
AND p.post_type = :regular
GROUP BY
t.id
) AS new_values
ON ths.topic_id = new_values.topic_id
WHERE thsOrig.topic_id = ths.topic_id
SQL
# we may end up update 2x batch size, this is ok
# we need to update 1 batch of high scoring topics
# we need to update a second batch of recently bumped topics
sql = <<~SQL
WITH topic_ids AS (
SELECT topic_id FROM (
SELECT th3.topic_id FROM topic_hot_scores th3
JOIN topics t3 on t3.id = th3.topic_id
ORDER BY t3.bumped_at DESC
LIMIT :max
) Y
UNION ALL
SELECT topic_id FROM (
SELECT th2.topic_id FROM topic_hot_scores th2
ORDER BY th2.score DESC, th2.recent_first_bumped_at DESC NULLS LAST
LIMIT :max
) X
)
UPDATE topic_hot_scores ths
SET score = (
CASE WHEN topics.created_at > :recent_cutoff
THEN ths.recent_likes ELSE topics.like_count END
) /
(EXTRACT(EPOCH FROM (:now - topics.created_at)) / 3600 + 2) ^ :gravity
+
CASE WHEN ths.recent_first_bumped_at IS NULL THEN 0 ELSE
(ths.recent_likes + ths.recent_posters - 1) /
(EXTRACT(EPOCH FROM (:now - recent_first_bumped_at)) / 3600 + 2) ^ :gravity
END
,
updated_at = :now
FROM topics
WHERE topics.id IN (
SELECT topic_id FROM topic_ids
) AND ths.topic_id = topics.id
SQL
DB.exec(sql, args)
そして、フォーラムのデフォルトの問題であっても、私の個人設定に触れたり変更したりすることは、そのようなことです。
）