diff --git a/lib/arel/nodes/sql_literal.rb b/lib/arel/nodes/sql_literal.rb
index 6471469d9fb8ade306b06f8bb0c52e953c0fd8bb..7299fb1d45d313b204a84e004d7aa29c12c6e9d6 100644
--- a/lib/arel/nodes/sql_literal.rb
+++ b/lib/arel/nodes/sql_literal.rb
@@ -5,6 +5,10 @@ def count distinct = false
         Count.new [self], distinct
       end
 
+      def sum
+        Nodes::Sum.new [self], Nodes::SqlLiteral.new('sum_id')
+      end
+
       def maximum
         Nodes::Max.new [self], Nodes::SqlLiteral.new('max_id')
       end