o.diff

diff --git a/activerecord/lib/active_record/connection_adapters/column.rb b/activerecord/lib/active_record/connection_adapters/column.rb
index af307b5..4037e316 100644
--- a/activerecord/lib/active_record/connection_adapters/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/column.rb
@@ -31,7 +31,7 @@ module ActiveRecord
       # It will be mapped to one of the standard Rails SQL types in the <tt>type</tt> attribute.
       # +null+ determines if this column allows +NULL+ values.
       def initialize(name, default, cast_type, sql_type = nil, null = true)
-        @name             = name
+        @name             = name.freeze
         @cast_type        = cast_type
         @sql_type         = sql_type
         @null             = null