diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index dead555cca..3893292cee 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,17 @@
+*   Calling `delete_all` on an unloaded `CollectionProxy` no longer
+    generates a SQL statement containing each id of the collection:
+
+    Before:
+
+        DELETE FROM `model` WHERE `model`.`parent_id` = 1
+        AND `model`.`id` IN (1, 2, 3...)
+
+    After:
+
+        DELETE FROM `model` WHERE `model`.`parent_id` = 1
+
+    *Eileen M. Uchitelle*, *Aaron Patterson*
+
 *   Fixed error for aggregate methods (`empty?`, `any?`, `count`) with `select`
     which created invalid SQL.