diff --git a/app/views/tag_subscriptions/index.html.erb b/app/views/tag_subscriptions/index.html.erb
index 614f46e3b..950cd5bab 100644
--- a/app/views/tag_subscriptions/index.html.erb
+++ b/app/views/tag_subscriptions/index.html.erb
@@ -19,7 +19,7 @@
             <td>
               <%= link_to "edit", edit_tag_subscription_path(tag_subscription) %>
               | <%= link_to "delete", tag_subscription_path(tag_subscription), :method => :delete, :data => {:confirm => "Are you sure you want to delete this subscription?"} %>
-              | <%= link_to "posts", posts_path(:tags => "sub:#{tag_subscription.creator.name}:#{tag_subscription.name}") %>
+              | <%= link_to "posts", posts_path(:tags => "sub:#{tag_subscription.creator.name}:#{tag_subscription.name}"), :rel => "nofollow" %>
             </td>
           </tr>
         <% end %>
diff --git a/db/migrate/20160219004022_add_trigram_index_to_pools.rb b/db/migrate/20160219004022_add_trigram_index_to_pools.rb
new file mode 100644
index 000000000..d8e847fd5
--- /dev/null
+++ b/db/migrate/20160219004022_add_trigram_index_to_pools.rb
@@ -0,0 +1,11 @@
+class AddTrigramIndexToPools < ActiveRecord::Migration
+  def up
+    execute "create extension pg_trgm"
+    execute "create index index_pools_on_name_trgm on pools using gin (name gin_trgm_ops)"
+  end
+
+  def down
+    execute "drop index index_pools_on_name_trgm"
+    execute "drop extension pg_trgm"
+  end
+end
diff --git a/db/migrate/20160219010854_add_trigram_indexes_to_artists.rb b/db/migrate/20160219010854_add_trigram_indexes_to_artists.rb
new file mode 100644
index 000000000..6f99cd9ab
--- /dev/null
+++ b/db/migrate/20160219010854_add_trigram_indexes_to_artists.rb
@@ -0,0 +1,13 @@
+class AddTrigramIndexesToArtists < ActiveRecord::Migration
+  def up
+    execute "create index index_artists_on_name_trgm on artists using gin (name gin_trgm_ops)"
+    execute "create index index_artists_on_group_name_trgm on artists using gin (group_name gin_trgm_ops)"
+    execute "create index index_artists_on_other_names_trgm on artists using gin (other_names gin_trgm_ops)"
+  end
+
+  def down
+    execute "drop index index_artists_on_other_names_trgm"
+    execute "drop index index_artists_on_group_name_trgm"
+    execute "drop index index_artists_on_name_trgm"
+  end
+end
diff --git a/db/scripts.sql b/db/scripts.sql
index 764e84b84..1465c4010 100644
--- a/db/scripts.sql
+++ b/db/scripts.sql
@@ -78,7 +78,6 @@ SELECT
 'table hit rate' AS name,
 sum(heap_blks_hit) / nullif(sum(heap_blks_hit) + sum(heap_blks_read),0) AS ratio
 FROM pg_statio_user_tables;
-);
 
 
 -- index hit rate
diff --git a/db/structure.sql b/db/structure.sql
index d8ea7849f..a196a9229 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -3,6 +3,7 @@
 --
 
 SET statement_timeout = 0;
+SET lock_timeout = 0;
 SET client_encoding = 'UTF8';
 SET standard_conforming_strings = on;
 SET check_function_bodies = false;
@@ -22,6 +23,20 @@ CREATE EXTENSION IF NOT EXISTS plpgsql WITH SCHEMA pg_catalog;
 COMMENT ON EXTENSION plpgsql IS 'PL/pgSQL procedural language';
 
 
+--
+-- Name: pg_trgm; Type: EXTENSION; Schema: -; Owner: -
+--
+
+CREATE EXTENSION IF NOT EXISTS pg_trgm WITH SCHEMA public;
+
+
+--
+-- Name: EXTENSION pg_trgm; Type: COMMENT; Schema: -; Owner: -
+--
+
+COMMENT ON EXTENSION pg_trgm IS 'text similarity measurement and index searching based on trigrams';
+
+
 SET search_path = public, pg_catalog;
 
 --
@@ -421,8 +436,8 @@ CREATE TABLE advertisement_hits (
     id integer NOT NULL,
     advertisement_id integer NOT NULL,
     ip_addr inet NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -459,8 +474,8 @@ CREATE TABLE advertisements (
     height integer NOT NULL,
     file_name character varying(255) NOT NULL,
     is_work_safe boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -490,8 +505,8 @@ ALTER SEQUENCE advertisements_id_seq OWNED BY advertisements.id;
 CREATE TABLE amazon_backups (
     id integer NOT NULL,
     last_id integer,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -557,8 +572,8 @@ CREATE TABLE artist_commentaries (
     original_description text,
     translated_title text,
     translated_description text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -594,8 +609,8 @@ CREATE TABLE artist_commentary_versions (
     original_description text,
     translated_title text,
     translated_description text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -627,8 +642,8 @@ CREATE TABLE artist_urls (
     artist_id integer NOT NULL,
     url text NOT NULL,
     normalized_url text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -666,8 +681,8 @@ CREATE TABLE artist_versions (
     group_name character varying(255),
     url_string text,
     is_banned boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -703,8 +718,8 @@ CREATE TABLE artists (
     other_names text,
     other_names_index tsvector,
     group_name character varying(255),
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -737,8 +752,8 @@ CREATE TABLE bans (
     reason text NOT NULL,
     banner_id integer NOT NULL,
     expires_at timestamp without time zone NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -804,8 +819,8 @@ CREATE TABLE comment_votes (
     comment_id integer NOT NULL,
     user_id integer NOT NULL,
     score integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -840,8 +855,8 @@ CREATE TABLE comments (
     ip_addr inet NOT NULL,
     body_index tsvector NOT NULL,
     score integer DEFAULT 0 NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     updater_id integer,
     updater_ip_addr inet,
     do_not_bump_post boolean DEFAULT false NOT NULL,
@@ -882,8 +897,8 @@ CREATE TABLE delayed_jobs (
     locked_at timestamp without time zone,
     failed_at timestamp without time zone,
     locked_by character varying(255),
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     queue character varying(255)
 );
 
@@ -953,8 +968,8 @@ CREATE TABLE dmails (
     message_index tsvector NOT NULL,
     is_read boolean DEFAULT false NOT NULL,
     is_deleted boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     creator_ip_addr inet DEFAULT '127.0.0.1'::inet NOT NULL
 );
 
@@ -2054,8 +2069,8 @@ CREATE TABLE forum_posts (
     body text NOT NULL,
     text_index tsvector NOT NULL,
     is_deleted boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2157,8 +2172,8 @@ CREATE TABLE forum_topics (
     is_locked boolean DEFAULT false NOT NULL,
     is_deleted boolean DEFAULT false NOT NULL,
     text_index tsvector NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     category_id integer DEFAULT 0 NOT NULL
 );
 
@@ -2191,8 +2206,8 @@ CREATE TABLE ip_bans (
     creator_id integer NOT NULL,
     ip_addr inet NOT NULL,
     reason text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2224,8 +2239,8 @@ CREATE TABLE janitor_trials (
     creator_id integer NOT NULL,
     user_id integer NOT NULL,
     original_level integer,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     status character varying(255) DEFAULT 'active'::character varying NOT NULL
 );
 
@@ -2257,8 +2272,8 @@ CREATE TABLE key_values (
     id integer NOT NULL,
     key character varying(255) NOT NULL,
     value text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2289,8 +2304,8 @@ CREATE TABLE mod_actions (
     id integer NOT NULL,
     creator_id integer NOT NULL,
     description text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2322,8 +2337,8 @@ CREATE TABLE news_updates (
     message text NOT NULL,
     creator_id integer NOT NULL,
     updater_id integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2362,8 +2377,8 @@ CREATE TABLE note_versions (
     height integer NOT NULL,
     is_active boolean DEFAULT true NOT NULL,
     body text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     version integer DEFAULT 0 NOT NULL
 );
 
@@ -2402,8 +2417,8 @@ CREATE TABLE notes (
     is_active boolean DEFAULT true NOT NULL,
     body text NOT NULL,
     body_index tsvector NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     version integer DEFAULT 0 NOT NULL
 );
 
@@ -2468,8 +2483,8 @@ CREATE TABLE pool_versions (
     post_ids text DEFAULT ''::text NOT NULL,
     updater_id integer NOT NULL,
     updater_ip_addr inet NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     name character varying(255)
 );
 
@@ -2506,8 +2521,8 @@ CREATE TABLE pools (
     post_ids text DEFAULT ''::text NOT NULL,
     post_count integer DEFAULT 0 NOT NULL,
     is_deleted boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     category character varying(255) DEFAULT 'series'::character varying NOT NULL
 );
 
@@ -2541,8 +2556,8 @@ CREATE TABLE post_appeals (
     creator_id integer NOT NULL,
     creator_ip_addr integer NOT NULL,
     reason text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2573,8 +2588,8 @@ CREATE TABLE post_disapprovals (
     id integer NOT NULL,
     user_id integer NOT NULL,
     post_id integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     reason character varying(255) DEFAULT 'legacy'::character varying,
     message text
 );
@@ -2610,8 +2625,8 @@ CREATE TABLE post_flags (
     creator_ip_addr inet NOT NULL,
     reason text,
     is_resolved boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2640,8 +2655,8 @@ ALTER SEQUENCE post_flags_id_seq OWNED BY post_flags.id;
 
 CREATE TABLE post_versions (
     id integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     post_id integer NOT NULL,
     tags text DEFAULT ''::text NOT NULL,
     rating character(1),
@@ -2680,8 +2695,8 @@ CREATE TABLE post_votes (
     post_id integer NOT NULL,
     user_id integer NOT NULL,
     score integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2710,8 +2725,8 @@ ALTER SEQUENCE post_votes_id_seq OWNED BY post_votes.id;
 
 CREATE TABLE posts (
     id integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     up_score integer DEFAULT 0 NOT NULL,
     down_score integer DEFAULT 0 NOT NULL,
     score integer DEFAULT 0 NOT NULL,
@@ -2827,8 +2842,8 @@ CREATE TABLE tag_aliases (
     creator_ip_addr inet NOT NULL,
     forum_topic_id integer,
     status text DEFAULT 'pending'::text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     post_count integer DEFAULT 0 NOT NULL
 );
 
@@ -2865,8 +2880,8 @@ CREATE TABLE tag_implications (
     creator_ip_addr inet NOT NULL,
     forum_topic_id integer,
     status text DEFAULT 'pending'::text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2902,8 +2917,8 @@ CREATE TABLE tag_subscriptions (
     is_public boolean DEFAULT true NOT NULL,
     last_accessed_at timestamp without time zone,
     is_opted_in boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -2937,8 +2952,8 @@ CREATE TABLE tags (
     category integer DEFAULT 0 NOT NULL,
     related_tags text,
     related_tags_updated_at timestamp without time zone,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     is_locked boolean DEFAULT false NOT NULL
 );
 
@@ -2971,8 +2986,8 @@ CREATE TABLE transaction_log_items (
     category character varying(255),
     user_id integer,
     data text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -3012,8 +3027,8 @@ CREATE TABLE uploads (
     backtrace text,
     post_id integer,
     md5_confirmation character varying(255),
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     server text,
     parent_id integer
 );
@@ -3048,8 +3063,8 @@ CREATE TABLE user_feedback (
     creator_id integer NOT NULL,
     category character varying(255) NOT NULL,
     body text NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -3085,8 +3100,8 @@ CREATE TABLE user_name_change_requests (
     desired_name character varying(255),
     change_reason text,
     rejection_reason text,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -3117,8 +3132,8 @@ CREATE TABLE user_password_reset_nonces (
     id integer NOT NULL,
     key character varying(255) NOT NULL,
     email character varying(255) NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone
 );
 
 
@@ -3147,8 +3162,8 @@ ALTER SEQUENCE user_password_reset_nonces_id_seq OWNED BY user_password_reset_no
 
 CREATE TABLE users (
     id integer NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     name character varying(255) NOT NULL,
     password_hash character varying(255) NOT NULL,
     email character varying(255),
@@ -3210,8 +3225,8 @@ CREATE TABLE wiki_page_versions (
     title character varying(255) NOT NULL,
     body text NOT NULL,
     is_locked boolean NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     other_names text
 );
 
@@ -3246,8 +3261,8 @@ CREATE TABLE wiki_pages (
     body text NOT NULL,
     body_index tsvector NOT NULL,
     is_locked boolean DEFAULT false NOT NULL,
-    created_at timestamp without time zone NOT NULL,
-    updated_at timestamp without time zone NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
     updater_id integer,
     other_names text,
     other_names_index tsvector
@@ -4851,10 +4866,10 @@ CREATE INDEX index_artist_versions_on_updater_id ON artist_versions USING btree
 
 
 --
--- Name: index_artists_on_group_name; Type: INDEX; Schema: public; Owner: -; Tablespace: 
+-- Name: index_artists_on_group_name_trgm; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --
 
-CREATE INDEX index_artists_on_group_name ON artists USING btree (group_name);
+CREATE INDEX index_artists_on_group_name_trgm ON artists USING gin (group_name gin_trgm_ops);
 
 
 --
@@ -4864,6 +4879,13 @@ CREATE INDEX index_artists_on_group_name ON artists USING btree (group_name);
 CREATE UNIQUE INDEX index_artists_on_name ON artists USING btree (name);
 
 
+--
+-- Name: index_artists_on_name_trgm; Type: INDEX; Schema: public; Owner: -; Tablespace: 
+--
+
+CREATE INDEX index_artists_on_name_trgm ON artists USING gin (name gin_trgm_ops);
+
+
 --
 -- Name: index_artists_on_other_names_index; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --
@@ -4871,6 +4893,13 @@ CREATE UNIQUE INDEX index_artists_on_name ON artists USING btree (name);
 CREATE INDEX index_artists_on_other_names_index ON artists USING gin (other_names_index);
 
 
+--
+-- Name: index_artists_on_other_names_trgm; Type: INDEX; Schema: public; Owner: -; Tablespace: 
+--
+
+CREATE INDEX index_artists_on_other_names_trgm ON artists USING gin (other_names gin_trgm_ops);
+
+
 --
 -- Name: index_bans_on_banner_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --
@@ -6579,20 +6608,6 @@ CREATE INDEX index_pool_versions_on_updater_ip_addr ON pool_versions USING btree
 CREATE INDEX index_pools_on_creator_id ON pools USING btree (creator_id);
 
 
---
--- Name: index_pools_on_lower_name; Type: INDEX; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE INDEX index_pools_on_lower_name ON pools USING btree (lower((name)::text));
-
-
---
--- Name: index_pools_on_name; Type: INDEX; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE INDEX index_pools_on_name ON pools USING btree (name);
-
-
 --
 -- Name: index_post_appeals_on_creator_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --
@@ -7285,3 +7300,7 @@ INSERT INTO schema_migrations (version) VALUES ('20150805010245');
 
 INSERT INTO schema_migrations (version) VALUES ('20151217213321');
 
+INSERT INTO schema_migrations (version) VALUES ('20160219004022');
+
+INSERT INTO schema_migrations (version) VALUES ('20160219010854');
+