Make implicit order column configurable

When calling ordered finder methods such as +first+ or +last+ without an
explicit order clause, ActiveRecord sorts records by primary key. This
can result in unpredictable and surprising behaviour when the primary
key is not an auto-incrementing integer, for example when it's a UUID.
This change makes it possible to override the column used for implicit
ordering such that +first+ and +last+ will return more predictable
results. For Example:

  class Project < ActiveRecord::Base
    self.implicit_order_column = "created_at"
  end

1 files changed, 17 insertions, 0 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 6186595a56..13cc486e7f 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,20 @@
+*   Make the implicit order column configurable.
+
+    When calling ordered finder methods such as +first+ or +last+ without an
+    explicit order clause, ActiveRecord sorts records by primary key. This can
+    result in unpredictable and surprising behaviour when the primary key is
+    not an auto-incrementing integer, for example when it's a UUID. This change
+    makes it possible to override the column used for implicit ordering such
+    that +first+ and +last+ will return more predictable results.
+
+    Example:
+
+        class Project < ActiveRecord::Base
+          self.implicit_order_column = "created_at"
+        end
+
+    *Tekin Suleyman*
+
 *   Bump minimum PostgreSQL version to 9.3.
 
     *Yasuo Honda*