Don't rely on the column for type casting reflections

3 files changed, 5 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 306588ac66..065a2cff01 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -55,9 +55,9 @@ module ActiveRecord
 
       # Implements the ids writer method, e.g. foo.item_ids= for Foo.has_many :items
       def ids_writer(ids)
-        pk_column = reflection.primary_key_column
+        pk_type = reflection.primary_key_type
         ids = Array(ids).reject { |id| id.blank? }
-        ids.map! { |i| pk_column.type_cast_from_user(i) }
+        ids.map! { |i| pk_type.type_cast_from_user(i) }
         replace(klass.find(ids).index_by { |r| r.id }.values_at(*ids))
       end
 
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 51c96373ee..28c39bdd5c 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -290,8 +290,8 @@ module ActiveRecord
         @foreign_key ||= options[:foreign_key] || derive_foreign_key
       end
 
-      def primary_key_column
-        klass.columns_hash[klass.primary_key]
+      def primary_key_type
+        klass.type_for_attribute(klass.primary_key)
       end
 
       def association_foreign_key
diff --git a/activerecord/lib/active_record/validations/uniqueness.rb b/activerecord/lib/active_record/validations/uniqueness.rb
index 2e7b1d7206..04e28a0cfe 100644
--- a/activerecord/lib/active_record/validations/uniqueness.rb
+++ b/activerecord/lib/active_record/validations/uniqueness.rb
@@ -48,7 +48,7 @@ module ActiveRecord
       def build_relation(klass, table, attribute, value) #:nodoc:
         if reflection = klass._reflect_on_association(attribute)
           attribute = reflection.foreign_key
-          value = value.attributes[reflection.primary_key_column.name] unless value.nil?
+          value = value.attributes[reflection.klass.primary_key] unless value.nil?
         end
 
         attribute_name = attribute.to_s