Unscope update_column(s) query to ignore default scope

When applying default_scope to a class with a where clause, using
update_column(s) could generate a query that would not properly update
the record due to the where clause from the default_scope being applied
to the update query.

    class User < ActiveRecord::Base
      default_scope where(active: true)
    end

    user = User.first
    user.active = false
    user.save!

    user.update_column(:active, true) # => false

In this situation we want to skip the default_scope clause and just
update the record based on the primary key. With this change:

    user.update_column(:active, true) # => true

Backport of #8436 fix.

Conflicts:
	activerecord/CHANGELOG.md
	activerecord/lib/active_record/persistence.rb
	activerecord/test/cases/persistence_test.rb

3 files changed, 35 insertions, 1 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 66c3222a25..f12094ab1e 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,5 +1,31 @@
 ## Rails 3.2.10 (unreleased)
 
+*   Unscope `update_column(s)` query to ignore default scope.
+
+    When applying `default_scope` to a class with a where clause, using
+    `update_column(s)` could generate a query that would not properly update
+    the record due to the where clause from the `default_scope` being applied
+    to the update query.
+
+        class User < ActiveRecord::Base
+          default_scope where(active: true)
+        end
+
+        user = User.first
+        user.active = false
+        user.save!
+
+        user.update_column(:active, true) # => false
+
+    In this situation we want to skip the default_scope clause and just
+    update the record based on the primary key. With this change:
+
+        user.update_column(:active, true) # => true
+
+    Backport of #8436 fix.
+
+    *Carlos Antonio da Silva*
+
 *   Fix performance problem with primary_key method in PostgreSQL adapter when having many schemas.
     Uses pg_constraint table instead of pg_depend table which has many records in general.
     Fix #8414
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb
index fd3380a53c..36b6b5fce2 100644
--- a/activerecord/lib/active_record/persistence.rb
+++ b/activerecord/lib/active_record/persistence.rb
@@ -194,7 +194,7 @@ module ActiveRecord
       raise ActiveRecordError, "#{name} is marked as readonly" if self.class.readonly_attributes.include?(name)
       raise ActiveRecordError, "can not update on a new record object" unless persisted?
 
-      updated_count = self.class.update_all({ name => value }, self.class.primary_key => id)
+      updated_count = self.class.unscoped.update_all({ name => value }, self.class.primary_key => id)
 
       raw_write_attribute(name, value)
 
diff --git a/activerecord/test/cases/persistence_test.rb b/activerecord/test/cases/persistence_test.rb
index a35cb3c4a5..00dc1f6d72 100644
--- a/activerecord/test/cases/persistence_test.rb
+++ b/activerecord/test/cases/persistence_test.rb
@@ -519,6 +519,14 @@ class PersistencesTest < ActiveRecord::TestCase
     assert return_value
   end
 
+  def test_update_column_with_default_scope
+    developer = DeveloperCalledDavid.first
+    developer.name = 'John'
+    developer.save!
+
+    assert developer.update_column(:name, 'Will'), 'did not update record due to default scope'
+  end
+
   def test_update_attributes
     topic = Topic.find(1)
     assert !topic.approved?