.. _version_5.2.5:

=============
Version 5.2.5
=============

Released on 2023-03-20.

.. NOTE::

    If you are upgrading a cluster, you must be running CrateDB 4.0.2 or higher
    before you upgrade to 5.2.5.

    We recommend that you upgrade to the latest 5.1 release before moving to
    5.2.5.

    A rolling upgrade from 5.1.x to 5.2.5 is supported.
    Before upgrading, you should `back up your data`_.

.. WARNING::

    Tables that were created before CrateDB 4.x will not function with 5.x
    and must be recreated before moving to 5.x.x.

    You can recreate tables using ``COPY TO`` and ``COPY FROM`` or by
    `inserting the data into a new table`_.

.. _back up your data: https://crate.io/docs/crate/reference/en/latest/admin/snapshots.html
.. _inserting the data into a new table: https://crate.io/docs/crate/reference/en/latest/admin/system-information.html#tables-need-to-be-recreated



.. rubric:: Table of Contents

.. contents::
   :local:

See the :ref:`version_5.2.0` release notes for a full list of changes in the
5.2 series.

Fixes
=====

- Fixed an issue that caused nested join queries to return incorrect
  results because a ``WHERE`` clause filter referencing a parent join was
  discarded by the planner. Example::

    SELECT * FROM t1 JOIN t2 ON t1.a = t2.b JOIN t3 ON t2.c = t3.d WHERE t1.x = t3.d

  In this case, the ``WHERE`` clause filter ``t1.x = t3.d`` was discarded.

