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

Fixes #8436.

1 files changed, 26 insertions, 0 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 4e48c386bd..e79c7cb64f 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,5 +1,31 @@
 ## Rails 4.0.0 (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
+
+    Fixes #8436.
+
+    *Carlos Antonio da Silva*
+
 *   SQLite adapter no longer corrupts binary data if the data contains `%00`.
 
     *Chris Feist*