2 files changed, 8 insertions, 16 deletions
diff --git a/activerecord/lib/active_record/associations/association_scope.rb b/activerecord/lib/active_record/associations/association_scope.rb
index 6cc401e6cc..6f8b76abda 100644
--- a/activerecord/lib/active_record/associations/association_scope.rb
+++ b/activerecord/lib/active_record/associations/association_scope.rb
@@ -20,31 +20,19 @@ module ActiveRecord
         # It's okay to just apply all these like this. The options will only be present if the
         # association supports that option; this is enforced by the association builder.
         scope = scope.apply_finder_options(options.slice(
-          :readonly, :include, :order, :limit, :joins, :group, :having, :offset))
+          :readonly, :include, :order, :limit, :joins, :group, :having, :offset, :select))
 
         if options[:through] && !options[:include]
           scope = scope.includes(source_options[:include])
         end
 
-        if select = select_value
-          scope = scope.select(select)
-        end
+        scope = scope.uniq if options[:uniq]
 
         add_constraints(scope)
       end
 
       private
 
-      def select_value
-        select_value = options[:select]
-
-        if reflection.collection?
-          select_value ||= options[:uniq] && "DISTINCT #{reflection.quoted_table_name}.*"
-        end
-
-        select_value
-      end
-
       def add_constraints(scope)
         tables = construct_tables
 
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index cec876149c..362f1053cd 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -344,8 +344,12 @@ module ActiveRecord
           if options[:counter_sql]
             interpolate(options[:counter_sql])
           else
-            # replace the SELECT clause with COUNT(*), preserving any hints within /* ... */
-            interpolate(options[:finder_sql]).sub(/SELECT\b(\/\*.*?\*\/ )?(.*)\bFROM\b/im) { "SELECT #{$1}COUNT(*) FROM" }
+            # replace the SELECT clause with COUNT(SELECTS), preserving any hints within /* ... */
+            interpolate(options[:finder_sql]).sub(/SELECT\b(\/\*.*?\*\/ )?(.*)\bFROM\b/im) do
+              count_with = $2.to_s
+              count_with = '*' if count_with.blank? || count_with =~ /,/
+              "SELECT #{$1}COUNT(#{count_with}) FROM"
+            end
           end
         end