2 files changed, 8 insertions, 1 deletions
diff --git a/lib/arel/visitors/mysql.rb b/lib/arel/visitors/mysql.rb
index 594fd5504a..afffd37f9b 100644
--- a/lib/arel/visitors/mysql.rb
+++ b/lib/arel/visitors/mysql.rb
@@ -10,6 +10,11 @@ module Arel
         super
       end
 
+      def visit_Arel_Nodes_SelectCore o
+        o.froms ||= Arel.sql('DUAL')
+        super
+      end
+
       def visit_Arel_Nodes_UpdateStatement o
         [
           "UPDATE #{visit o.relation}",
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 1412797fb5..b6af47cc57 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -48,6 +48,7 @@ module Arel
           ("WHERE #{wheres.map { |x| visit x }.join ' AND '}" unless wheres.empty?)
         ].compact.join ' '
       end
+
       def visit_Arel_Nodes_InsertStatement o
         [
           "INSERT INTO #{visit o.relation}",
@@ -61,7 +62,8 @@ module Arel
       end
 
       def visit_Arel_Nodes_Exists o
-        "EXISTS (#{visit o.select_stmt})"
+        "EXISTS (#{visit o.select_stmt})#{
+          o.alias ? " AS #{visit o.alias}" : ''}"
       end
 
       def visit_Arel_Nodes_Values o