.. _version_3.3.6:

=============
Version 3.3.6
=============

Released on 2019/09/27.

.. NOTE::

    If you are upgrading a cluster, you must be running CrateDB 2.0.4 or higher
    before you upgrade to 3.3.6.

    We recommend that you upgrade to the latest 3.2 release before moving to
    3.3.6.

    If you want to perform a `rolling upgrade`_, your current CrateDB version
    number must be at least :ref:`version_3.3.0`. Any upgrade from a version
    prior to this will require a `full restart upgrade`_.

    When restarting, CrateDB will migrate indexes to a newer format. Depending
    on the amount of data, this may delay node start-up time.

    Please consult the :ref:`version_3.3.0_upgrade_notes` before upgrading.

.. WARNING::

    Tables that were created prior to upgrading to CrateDB 2.x will not
    function with 3.3 and must be recreated before moving to 3.3.x.

    You can recreate tables using ``COPY TO`` and ``COPY FROM`` while running a
    2.x release into a new table, or by `inserting the data into a new table`_.

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

.. _rolling upgrade: https://crate.io/docs/crate/howtos/en/latest/admin/rolling-upgrade.html
.. _full restart upgrade: https://crate.io/docs/crate/howtos/en/latest/admin/full-restart-upgrade.html
.. _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:


Changelog
=========


Fixes
-----

- Fixed an issue that could prevent accounted memory from being properly
  de-accounted on queries using ``hyperloglog_distinct``, leading clients to
  eventually receive ``CircuitBreakingException`` error messages and also
  breaking internal recovery operations.

- Removed a case where a ``NullPointerException`` was logged if a HTTP client
  disconnected before a pending response could be sent to the client.
