.. _version_4.2.6:

=============
Version 4.2.6
=============

Released on 2020-10-08.

.. NOTE::

    If you are upgrading a cluster, you must be running CrateDB 4.0.2 or higher
    before you upgrade to 4.2.6.

    We recommend that you upgrade to the latest 4.1 release before moving to
    4.2.6.

    A rolling upgrade from 4.1.7+ to 4.2.6 is supported.

    Before upgrading, you should `back up your data`_.

.. _back up your data: https://crate.io/docs/crate/reference/en/latest/admin/snapshots.html



.. rubric:: Table of Contents

.. contents::
   :local:


See the :ref:`version_4.2.0` release notes for a full list of changes in the
4.2 series.


Fixes
=====

- Fixed a regression introduced in 4.2 which prevented ``DELETE FROM ...``
  statements with the :ref:`subquery <gloss-subquery>` :ref:`expression
  <gloss-expression>` in the where clause from complete deletion of the
  matching partitions in partitioned tables.

- Fixed an issue that prevented casts from ``DOUBLE PRECISION`` to ``REAL`` for
  the minimal supported ``REAL`` number ``-3.4028235e38``.

- Fixed an issue that prevented an access to the properties of object type
  arguments in JavaScript :ref:`user-defined functions
  <user-defined-functions>`.

- Fixed a regression introduced in 4.2 that could cause :ref:`subscript
  expressions <sql-subscripts>` to fail with a ``Base argument to subscript
  must be an object, not null`` or ``Can't handle Symbol`` error.

- Fixed an issue causing a node crash due to OOM when running the ``analyze``
  on large tables.

- Fixed an issue that caused queries involving a JOIN operation on system
  tables like ``sys.cluster`` to fail.

- Changed the memory reservation and circuit breaker behavior for ``INSERT FROM
  QUERY`` operations to allow for more concurrent operations. After the change
  introduced in 4.2.5, individual operations could reserve too much memory,
  causing other operations to fail with a circuit breaker exception.
