3 files changed, 25 insertions, 1 deletions
diff --git a/lib/arel/predications.rb b/lib/arel/predications.rb
index 08cbf16d9d..36eae074a8 100644
--- a/lib/arel/predications.rb
+++ b/lib/arel/predications.rb
@@ -42,7 +42,17 @@ module Arel
           Nodes::Between.new(self, Nodes::And.new([other.begin, other.end]))
         end
       else
-        Nodes::In.new self, other
+        if other.include?(nil)
+          if other.size > 1
+            set  = Nodes::In.new self, other.compact
+            null = Nodes::Equality.new self, nil
+            Nodes::Or.new set, null
+          else
+            Nodes::Equality.new self, nil
+          end
+        else
+          Nodes::In.new self, other
+        end
       end
     end
 
diff --git a/lib/arel/visitors.rb b/lib/arel/visitors.rb
index 8410b2b912..f2644d7205 100644
--- a/lib/arel/visitors.rb
+++ b/lib/arel/visitors.rb
@@ -10,6 +10,7 @@ require 'arel/visitors/join_sql'
 require 'arel/visitors/where_sql'
 require 'arel/visitors/order_clauses'
 require 'arel/visitors/dot'
+require 'arel/visitors/ibm_db'
 
 module Arel
   module Visitors
@@ -22,6 +23,7 @@ module Arel
       'oracle_enhanced' => Arel::Visitors::Oracle,
       'sqlite'          => Arel::Visitors::SQLite,
       'sqlite3'         => Arel::Visitors::SQLite,
+      'ibm_db'          => Arel::Visitors::IBM_DB,
     }
 
     ENGINE_VISITORS = Hash.new do |hash, engine|
diff --git a/lib/arel/visitors/ibm_db.rb b/lib/arel/visitors/ibm_db.rb
new file mode 100644
index 0000000000..0c26a3ae9e
--- /dev/null
+++ b/lib/arel/visitors/ibm_db.rb
@@ -0,0 +1,12 @@
+module Arel
+  module Visitors
+    class IBM_DB < Arel::Visitors::ToSql
+      private
+
+      def visit_Arel_Nodes_Limit o
+        "FETCH FIRST #{visit o.expr} ROWS ONLY"
+      end
+
+    end
+  end
+end