diff --git a/lib/topic_query_sql.rb b/lib/topic_query_sql.rb
index 465737ce125..97d45982090 100644
--- a/lib/topic_query_sql.rb
+++ b/lib/topic_query_sql.rb
@@ -5,16 +5,10 @@ module TopicQuerySQL
 
   class << self
 
-    # use the constants in conjuction with COALESCE to determine the order with regard to pinned
-    # topics that have been cleared by the user. There might be a cleaner way to do this.
     def lowest_date
       "2010-01-01"
     end
 
-    def highest_date
-      "infinity"
-    end
-
     def order_by_category_sql(dir)
       "CASE WHEN categories.id = #{SiteSetting.uncategorized_category_id.to_i} THEN '' ELSE categories.name END #{dir}"
     end
@@ -23,17 +17,18 @@ module TopicQuerySQL
     def order_with_pinned_sql
       "CASE
         WHEN (COALESCE(topics.pinned_at, '#{lowest_date}') > COALESCE(tu.cleared_pinned_at, '#{lowest_date}'))
-          THEN '#{highest_date}'
-        ELSE topics.bumped_at
+          THEN topics.pinned_at + interval '9999 years'
+          ELSE topics.bumped_at
        END DESC"
     end
 
     # If you've clearned the pin, use bumped_at, otherwise put it at the top
     def order_nocategory_with_pinned_sql
       "CASE
-        WHEN topics.pinned_globally and (COALESCE(topics.pinned_at, '#{lowest_date}') > COALESCE(tu.cleared_pinned_at, '#{lowest_date}'))
-          THEN '#{highest_date}'
-        ELSE topics.bumped_at
+        WHEN topics.pinned_globally
+         AND (COALESCE(topics.pinned_at, '#{lowest_date}') > COALESCE(tu.cleared_pinned_at, '#{lowest_date}'))
+          THEN topics.pinned_at + interval '9999 years'
+          ELSE topics.bumped_at
        END DESC"
     end
 
@@ -42,7 +37,7 @@ module TopicQuerySQL
     end
 
     def order_nocategory_basic_bumped
-      "CASE WHEN topics.pinned_globally and (topics.pinned_at IS NOT NULL) THEN 0 ELSE 1 END, topics.bumped_at DESC"
+      "CASE WHEN topics.pinned_globally AND (topics.pinned_at IS NOT NULL) THEN 0 ELSE 1 END, topics.bumped_at DESC"
     end
 
     def order_top_for(score)
@@ -51,7 +46,7 @@ module TopicQuerySQL
 
     def order_top_with_pinned_category_for(score)
       # display pinned topics first
-      "CASE WHEN COALESCE(topics.pinned_at, '#{lowest_date}') > COALESCE(tu.cleared_pinned_at, '#{lowest_date}') THEN 1 ELSE 0 END DESC,
+      "CASE WHEN (COALESCE(topics.pinned_at, '#{lowest_date}') > COALESCE(tu.cleared_pinned_at, '#{lowest_date}')) THEN 0 ELSE 1 END,
        top_topics.#{score} DESC,
        topics.bumped_at DESC"
     end