db: add indexes on comment fields.

db/migrate/20220923010905_add_indexes_on_comments.rb

@@ -0,0 +1,11 @@
+class AddIndexesOnComments < ActiveRecord::Migration[7.0]
+  disable_ddl_transaction!
+
+  def change
+    add_index :comments, :score, if_not_exists: true, algorithm: :concurrently
+    add_index :comments, :is_deleted, where: "is_deleted = true", if_not_exists: true, algorithm: :concurrently
+    add_index :comments, :is_sticky, where: "is_sticky = true", if_not_exists: true, algorithm: :concurrently
+    add_index :comments, :do_not_bump_post, where: "do_not_bump_post = true", if_not_exists: true, algorithm: :concurrently
+    add_index :comments, :updater_id, where: "updater_id IS NOT NULL", if_not_exists: true, algorithm: :concurrently
+  end
+end

db/structure.sql

@@ -3676,6 +3676,27 @@ CREATE INDEX index_comments_on_creator_id_and_created_at ON public.comments USIN
 CREATE INDEX index_comments_on_creator_id_and_post_id ON public.comments USING btree (creator_id, post_id);
 
 
+--
+-- Name: index_comments_on_do_not_bump_post; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_do_not_bump_post ON public.comments USING btree (do_not_bump_post) WHERE (do_not_bump_post = true);
+
+
+--
+-- Name: index_comments_on_is_deleted; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_is_deleted ON public.comments USING btree (is_deleted) WHERE (is_deleted = true);
+
+
+--
+-- Name: index_comments_on_is_sticky; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_is_sticky ON public.comments USING btree (is_sticky) WHERE (is_sticky = true);
+
+
 --
 -- Name: index_comments_on_post_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -3683,6 +3704,20 @@ CREATE INDEX index_comments_on_creator_id_and_post_id ON public.comments USING b
 CREATE INDEX index_comments_on_post_id ON public.comments USING btree (post_id);
 
 
+--
+-- Name: index_comments_on_score; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_score ON public.comments USING btree (score);
+
+
+--
+-- Name: index_comments_on_updater_id; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_updater_id ON public.comments USING btree (updater_id) WHERE (updater_id IS NOT NULL);
+
+
 --
 -- Name: index_completed_user_upgrades_on_created_at; Type: INDEX; Schema: public; Owner: -
 --
@@ -6637,6 +6672,7 @@ INSERT INTO "schema_migrations" (version) VALUES
 ('20220919041622'),
 ('20220920224005'),
 ('20220921022408'),
-('20220922014326');
+('20220922014326'),
+('20220923010905');