1 files changed, 6 insertions, 0 deletions
diff --git a/activerecord/lib/arel/visitors/oracle12.rb b/activerecord/lib/arel/visitors/oracle12.rb
index 7061f06087..b092aa95e0 100644
--- a/activerecord/lib/arel/visitors/oracle12.rb
+++ b/activerecord/lib/arel/visitors/oracle12.rb
@@ -56,6 +56,12 @@ module Arel # :nodoc: all
         def visit_Arel_Nodes_BindParam(o, collector)
           collector.add_bind(o.value) { |i| ":a#{i}" }
         end
+
+        def is_distinct_from(o, collector)
+          collector << "DECODE("
+          collector = visit [o.left, o.right, 0, 1], collector
+          collector << ")"
+        end
     end
   end
 end