[DB] Improve performance of some wildcard text searches

Comments are consistently timing out. The others don't necessarily need this,
but it improves performance nevertheless

db/migrate/20230517155547_add_text_wildcard_search_index.rb

@@ -0,0 +1,17 @@
+class AddTextWildcardSearchIndex < ActiveRecord::Migration[7.0]
+  def up
+    add_gin_index :blips, :body
+    add_gin_index :comments, :body
+    add_gin_index :dmails, :body
+    add_gin_index :forum_posts, :body
+    add_gin_index :forum_topics, :title
+    add_gin_index :notes, :body
+    add_gin_index :user_feedback, :body
+    add_gin_index :wiki_pages, :body
+    add_gin_index :wiki_pages, :title
+  end
+
+  def add_gin_index(table, column)
+    execute("CREATE INDEX index_#{table}_on_lower_#{column}_trgm ON #{table} USING gin ((lower(#{column})) gin_trgm_ops)")
+  end
+end

db/structure.sql

@@ -3424,6 +3424,13 @@ CREATE INDEX index_bans_on_expires_at ON public.bans USING btree (expires_at);
 CREATE INDEX index_bans_on_user_id ON public.bans USING btree (user_id);
 
 
+--
+-- Name: index_blips_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_blips_on_lower_body_trgm ON public.blips USING gin (lower((body)::text) public.gin_trgm_ops);
+
+
 --
 -- Name: index_blips_on_to_tsvector_english_body; Type: INDEX; Schema: public; Owner: -
 --
@@ -3487,6 +3494,13 @@ CREATE INDEX index_comments_on_creator_id_and_post_id ON public.comments USING b
 CREATE INDEX index_comments_on_creator_ip_addr ON public.comments USING btree (creator_ip_addr);
 
 
+--
+-- Name: index_comments_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_comments_on_lower_body_trgm ON public.comments USING gin (lower(body) public.gin_trgm_ops);
+
+
 --
 -- Name: index_comments_on_post_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -3529,6 +3543,13 @@ CREATE INDEX index_dmails_on_is_deleted ON public.dmails USING btree (is_deleted
 CREATE INDEX index_dmails_on_is_read ON public.dmails USING btree (is_read);
 
 
+--
+-- Name: index_dmails_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_dmails_on_lower_body_trgm ON public.dmails USING gin (lower(body) public.gin_trgm_ops);
+
+
 --
 -- Name: index_dmails_on_owner_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -3599,6 +3620,13 @@ CREATE UNIQUE INDEX index_forum_post_votes_on_forum_post_id_and_creator_id ON pu
 CREATE INDEX index_forum_posts_on_creator_id ON public.forum_posts USING btree (creator_id);
 
 
+--
+-- Name: index_forum_posts_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_forum_posts_on_lower_body_trgm ON public.forum_posts USING gin (lower(body) public.gin_trgm_ops);
+
+
 --
 -- Name: index_forum_posts_on_to_tsvector_english_body; Type: INDEX; Schema: public; Owner: -
 --
@@ -3662,6 +3690,13 @@ CREATE INDEX index_forum_topics_on_creator_id ON public.forum_topics USING btree
 CREATE INDEX index_forum_topics_on_is_sticky_and_updated_at ON public.forum_topics USING btree (is_sticky, updated_at);
 
 
+--
+-- Name: index_forum_topics_on_lower_title_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_forum_topics_on_lower_title_trgm ON public.forum_topics USING gin (lower((title)::text) public.gin_trgm_ops);
+
+
 --
 -- Name: index_forum_topics_on_to_tsvector_english_title; Type: INDEX; Schema: public; Owner: -
 --
@@ -3753,6 +3788,13 @@ CREATE INDEX index_note_versions_on_updater_ip_addr ON public.note_versions USIN
 CREATE INDEX index_notes_on_creator_id_and_post_id ON public.notes USING btree (creator_id, post_id);
 
 
+--
+-- Name: index_notes_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_notes_on_lower_body_trgm ON public.notes USING gin (lower(body) public.gin_trgm_ops);
+
+
 --
 -- Name: index_notes_on_post_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -4195,6 +4237,13 @@ CREATE INDEX index_user_feedback_on_creator_id ON public.user_feedback USING btr
 CREATE INDEX index_user_feedback_on_creator_ip_addr ON public.user_feedback USING btree (creator_ip_addr);
 
 
+--
+-- Name: index_user_feedback_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_user_feedback_on_lower_body_trgm ON public.user_feedback USING gin (lower(body) public.gin_trgm_ops);
+
+
 --
 -- Name: index_user_feedback_on_to_tsvector_english_body; Type: INDEX; Schema: public; Owner: -
 --
@@ -4279,6 +4328,20 @@ CREATE INDEX index_wiki_page_versions_on_updater_ip_addr ON public.wiki_page_ver
 CREATE INDEX index_wiki_page_versions_on_wiki_page_id ON public.wiki_page_versions USING btree (wiki_page_id);
 
 
+--
+-- Name: index_wiki_pages_on_lower_body_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_wiki_pages_on_lower_body_trgm ON public.wiki_pages USING gin (lower(body) public.gin_trgm_ops);
+
+
+--
+-- Name: index_wiki_pages_on_lower_title_trgm; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_wiki_pages_on_lower_title_trgm ON public.wiki_pages USING gin (lower((title)::text) public.gin_trgm_ops);
+
+
 --
 -- Name: index_wiki_pages_on_other_names; Type: INDEX; Schema: public; Owner: -
 --
@@ -4640,6 +4703,7 @@ INSERT INTO "schema_migrations" (version) VALUES
 ('20230314170352'),
 ('20230316084945'),
 ('20230506161827'),
-('20230513074838');
+('20230513074838'),
+('20230517155547');