1 files changed, 137 insertions, 1 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 3bfaa59f06..52aaa2371d 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -4,6 +4,142 @@
 
     *Miklos Fazekas*
 
+*   Format the time string according to the precision of the time column.
+
+    *Ryuta Kamizono*
+
+*   Allow `:precision` option for time type columns.
+
+    *Ryuta Kamizono*
+
+*   Add `ActiveRecord::Base.suppress` to prevent the receiver from being saved
+    during the given block.
+
+    For example, here's a pattern of creating notifications when new comments
+    are posted. (The notification may in turn trigger an email, a push
+    notification, or just appear in the UI somewhere):
+
+        class Comment < ActiveRecord::Base
+          belongs_to :commentable, polymorphic: true
+          after_create -> { Notification.create! comment: self,
+            recipients: commentable.recipients }
+        end
+
+    That's what you want the bulk of the time. New comment creates a new
+    Notification. But there may well be off cases, like copying a commentable
+    and its comments, where you don't want that. So you'd have a concern
+    something like this:
+
+        module Copyable
+          def copy_to(destination)
+            Notification.suppress do
+              # Copy logic that creates new comments that we do not want triggering
+              # notifications.
+            end
+          end
+        end
+
+    *Michael Ryan*
+
+*   `:time` option added for `#touch`
+    Fixes #18905.
+
+    *Hyonjee Joo*
+
+*   Deprecated passing of `start` value to `find_in_batches` and `find_each`
+    in favour of `begin_at` value.
+
+    *Vipul A M*
+
+*   Add `foreign_key_exists?` method.
+
+    *Tõnis Simo*
+
+*   Use SQL COUNT and LIMIT 1 queries for `none?` and `one?` methods if no block or limit is given,
+    instead of loading the entire collection to memory.
+    This applies to relations (e.g. `User.all`) as well as associations (e.g. `account.users`)
+
+        # Before:
+
+        users.none?
+        # SELECT "users".* FROM "users"
+
+        users.one?
+        # SELECT "users".* FROM "users"
+
+        # After:
+
+        users.none?
+        # SELECT 1 AS one FROM "users" LIMIT 1
+
+        users.one?
+        # SELECT COUNT(*) FROM "users"
+
+    *Eugene Gilburg*
+
+*   Have `enum` perform type casting consistently with the rest of Active
+    Record, such as `where`.
+
+    *Sean Griffin*
+
+*   `scoping` no longer pollutes the current scope of sibling classes when using
+    STI. e.x.
+
+    StiOne.none.scoping do
+      StiTwo.all
+    end
+
+    Fixes #18806.
+
+    *Sean Griffin*
+
+*   `remove_reference` with `foreign_key: true` removes the foreign key before
+    removing the column. This fixes a bug where it was not possible to remove
+    the column on MySQL.
+
+    Fixes #18664.
+
+    *Yves Senn*
+
+*   `find_in_batches` now accepts an `:end_at` parameter that complements the `:start`
+     parameter to specify where to stop batch processing.
+
+    *Vipul A M*
+
+*   Fix rounding problem for PostgreSQL timestamp column.
+
+    If timestamp column have the precision, it need to format according to
+    the precision of timestamp column.
+
+    *Ryuta Kamizono*
+
+*   Respect the database default charset for `schema_migrations` table.
+
+    The charset of `version` column in `schema_migrations` table is depend
+    on the database default charset and collation rather than the encoding
+    of the connection.
+
+    *Ryuta Kamizono*
+
+*   Raise `ArgumentError` when passing `nil` or `false` to `Relation#merge`.
+
+    These are not valid values to merge in a relation so it should warn the users
+    early.
+
+    *Rafael Mendonça França*
+
+*   Use `SCHEMA` instead of `DB_STRUCTURE` for specifying structure file.
+
+    This makes the db:structure tasks consistent with test:load_structure.
+
+    *Dieter Komendera*
+
+*   Respect custom primary keys for associations when calling `Relation#where`
+
+    Fixes #18813.
+
+    *Sean Griffin*
+
 *   Fixed several edge cases which could result in a counter cache updating
     twice or not updating at all for `has_many` and `has_many :through`.
 
@@ -76,7 +212,7 @@
     *Sean Griffin*
 
 *   Values which would error while being sent to the database (such as an
-    ASCII-8BIT string with invalid UTF-8 bytes on Sqlite3), no longer error on
+    ASCII-8BIT string with invalid UTF-8 bytes on SQLite3), no longer error on
     assignment. They will still error when sent to the database, but you are
     given the ability to re-assign it to a valid value.