--- a/doc/changes/3.23.rst	Thu Jun 23 16:29:03 2016 +0200
+++ b/doc/changes/3.23.rst	Fri Jun 24 11:50:31 2016 +0200
@@ -9,4 +9,37 @@
   `CubicWebTC` either from the standard library as of Python 3.4 or through
   unittest2 package otherwise).
 
+Database handling
+-----------------
+
+* Most indexes and constraints will be rebuilt during the migration, because
+  they are now named after a md5 hash to control the name's size.
+
+* Index are renamed upon renaming of an entity type, so they are still
+  correctly tracked.
+
+* A new `db-check-index` command is added to `cubicweb-ctl`, to display the
+  differences between the indexes in the database and those expected by the
+  schema. It's recommended to run this command after the migration to 3.23 and
+  to adjust things manually for cases that are not easily handled by the
+  migration script, such as indexes of entity types that have been renamed. It
+  should be mostly about dropping extra indexes.
+
+
+Data-import
+-----------
+
+* Deprecated `MetaGenerator` in favor of slightly adapted API in
+  `MetadataGenerator` (more consistent, giving more control to sub-classes and
+  suitable for usage with the `MassiveObjectStore`)
+
+* Major cleanups of the `MassiveObjectStore` and its `PGHelper` companion
+  class:
+
+  - dropped a bunch of unnecessary / unused attributes
+  - refactored / renamed internal methods
+  - added support for a metadata generator, the now recommended way to control
+    metadata generation
+
+
 .. _subtests: https://docs.python.org/3/library/unittest.html#distinguishing-test-iterations-using-subtests