Commit a87ade7e authored by Benjamin Bach's avatar Benjamin Bach Committed by Tim Graham
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[1.6.x] Documented a current limitation of multiple table annotation; refs #10060.

Backport of 4b23a6c7 from master
parent 51dff0f5
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Original line number Diff line number Diff line
@@ -179,6 +179,17 @@ of the ``annotate()`` clause is a ``QuerySet``; this ``QuerySet`` can be
modified using any other ``QuerySet`` operation, including ``filter()``,
``order_by()``, or even additional calls to ``annotate()``.

.. admonition:: If in doubt, inspect the SQL query!

    In order to understand what happens in your query, consider inspecting the
    ``query`` property of your ``QuerySet``.

    For instance, combining multiple aggregations with ``annotate()`` will
    yield the wrong results, as `multiple tables are the cross joined`_,
    resulting in duplicate row aggregations.

.. _multiple tables are the cross joined: https://code.djangoproject.com/ticket/10060

Joins and aggregates
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