1 files changed, 2 insertions, 10 deletions
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb
index cf6673db2e..714d36e7c0 100644
--- a/activerecord/lib/active_record/persistence.rb
+++ b/activerecord/lib/active_record/persistence.rb
@@ -246,7 +246,7 @@ module ActiveRecord
       name = name.to_s
       verify_readonly_attribute(name)
       send("#{name}=", value)
-      save(validate: false)
+      save(validate: false) if changed?
     end
 
     # Updates the attributes of the model from the passed-in hash and saves the
@@ -495,15 +495,7 @@ module ActiveRecord
     end
 
     def relation_for_destroy
-      pk         = self.class.primary_key
-      column     = self.class.columns_hash[pk]
-      substitute = self.class.connection.substitute_at(column)
-
-      relation = self.class.unscoped.where(
-        self.class.arel_table[pk].eq(substitute))
-
-      relation.bind_values = [[column, id]]
-      relation
+      self.class.unscoped.where(self.class.primary_key => id)
     end
 
     def create_or_update(*args)