From 0066a4b42b3472c088eed945605a2cf0bfcc1362 Mon Sep 17 00:00:00 2001 From: dullbananas Date: Sat, 30 Dec 2023 14:28:38 -0700 Subject: [PATCH] update comment count in post trigger --- replaceable_schema.sql | 57 ++++++------------------------------------ 1 file changed, 7 insertions(+), 50 deletions(-) diff --git a/replaceable_schema.sql b/replaceable_schema.sql index 99ebca83d..be06ea276 100644 --- a/replaceable_schema.sql +++ b/replaceable_schema.sql @@ -202,7 +202,8 @@ CALL r.post_or_comment ('post'); CALL r.post_or_comment ('comment'); --- Create triggers that update counts in parent aggregates +-- Create triggers that update counts in parent aggregates (a trigger can run in response to deletion caused by +-- a foreign key with `ON DELETE CASCADE`, so the parent might not exist) CALL r.create_triggers ('comment', $$ WITH comment_group AS ( SELECT (comment).post_id, @@ -287,7 +288,8 @@ unused_person_aggregates_update_result AS ( CALL r.create_triggers ('post', $$ WITH post_group AS ( SELECT - (post).community_id, (post).creator_id, (post).local, coalesce(sum(count_diff), 0) AS posts FROM combined_transition_tables + (post).community_id, (post).creator_id, (post).local, coalesce(sum(count_diff), 0) AS posts, + coalesce(sum(count_diff * (SELECT comments FROM post_aggregates WHERE post_id = (post).id LIMIT 1)), 0) AS comments FROM combined_transition_tables WHERE NOT ((post).deleted OR (post).removed) @@ -307,7 +309,9 @@ CALL r.create_triggers ('post', $$ WITH post_group AS ( UPDATE community_aggregates AS a SET - posts = a.posts + post_group.posts FROM post_group + posts = a.posts + post_group.posts, + -- Update comment count when post is deleted, removed, or restored + comments = a.comments + post_group.comments FROM post_group WHERE a.community_id = post_group.community_id $$); @@ -329,53 +333,6 @@ CALL r.create_triggers ('person', $$ UPDATE coalesce(sum(count_diff), 0) AS users FROM combined_transition_tables WHERE (person).local) AS diff $$); --- For community_aggregates.comments, don't include comments of deleted or removed posts -CREATE FUNCTION r.update_comment_count_from_post () - RETURNS TRIGGER - LANGUAGE plpgsql - AS $$ -BEGIN - UPDATE - community_aggregates AS a - SET - comments = a.comments + diff.comments - FROM ( - SELECT - old_post.community_id, - sum(( - CASE WHEN new_post.deleted - AND new_post.removed THEN - -1 - ELSE - 1 - END) * post_aggregates.comments) AS comments - FROM - new_post - INNER JOIN old_post ON new_post.id = old_post.id - AND (new_post.deleted - AND new_post.removed) != (old_post.deleted - AND old_post.removed), - LATERAL ( - SELECT - * - FROM - post_aggregates - WHERE - post_id = new_post.id - LIMIT 1) AS post_aggregates - GROUP BY - old_post.community_id) AS diff -WHERE - a.community_id = diff.community_id; - RETURN NULL; -END -$$; - -CREATE TRIGGER comment_count - AFTER UPDATE ON post REFERENCING OLD TABLE AS old_post NEW TABLE AS new_post - FOR EACH STATEMENT - EXECUTE FUNCTION r.update_comment_count_from_post (); - -- Count subscribers for local communities CALL r.create_triggers ('community_follower', $$ UPDATE community_aggregates AS a