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Fixed #29573 -- Added links in aggregation topic guide.

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Vishvajit Pathak 2018-09-10 19:23:19 +05:30 committed by Tim Graham
parent 22e8ab0286
commit a48bc0cec9
1 changed files with 10 additions and 9 deletions
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19
docs/topics/db/aggregation.txt
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@ -149,19 +149,20 @@ Generating aggregates for each item in a ``QuerySet``
=====================================================
The second way to generate summary values is to generate an independent
summary for each object in a ``QuerySet``. For example, if you are retrieving
a list of books, you may want to know how many authors contributed to
each book. Each Book has a many-to-many relationship with the Author; we
summary for each object in a :class:`.QuerySet`. For example, if you are
retrieving a list of books, you may want to know how many authors contributed
to each book. Each Book has a many-to-many relationship with the Author; we
want to summarize this relationship for each book in the ``QuerySet``.
Per-object summaries can be generated using the ``annotate()`` clause.
When an ``annotate()`` clause is specified, each object in the ``QuerySet``
will be annotated with the specified values.
Per-object summaries can be generated using the
:meth:`~.QuerySet.annotate` clause. When an ``annotate()`` clause is
specified, each object in the ``QuerySet`` will be annotated with the
specified values.
The syntax for these annotations is identical to that used for the
``aggregate()`` clause. Each argument to ``annotate()`` describes an
aggregate that is to be calculated. For example, to annotate books with
the number of authors:
:meth:`~.QuerySet.aggregate` clause. Each argument to ``annotate()`` describes
an aggregate that is to be calculated. For example, to annotate books with the
number of authors:
.. code-block:: python