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@@ -4,15 +4,28 @@ Performing raw SQL queries
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.. currentmodule:: django.db.models
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-When the :doc:`model query APIs </topics/db/queries>` don't go far enough, you
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-can fall back to writing raw SQL. Django gives you two ways of performing raw
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-SQL queries: you can use :meth:`Manager.raw()` to `perform raw queries and
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-return model instances`__, or you can avoid the model layer entirely and
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-`execute custom SQL directly`__.
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+Django gives you two ways of performing raw SQL queries: you can use
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+:meth:`Manager.raw()` to `perform raw queries and return model instances`__, or
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+you can avoid the model layer entirely and `execute custom SQL directly`__.
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__ `performing raw queries`_
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__ `executing custom SQL directly`_
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+.. admonition:: Explore the ORM before using raw SQL!
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+
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+ The Django ORM provides many tools to express queries without writing raw
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+ SQL. For example:
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+
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+ * The :doc:`QuerySet API </ref/models/querysets>` is extensive.
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+ * You can :meth:`annotate <.QuerySet.annotate>` and :doc:`aggregate
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+ </topics/db/aggregation>` using many built-in :doc:`database functions
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+ </ref/models/database-functions>`. Beyond those, you can create
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+ :doc:`custom query expressions </ref/models/expressions/>`.
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+
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+ Before using raw SQL, explore :doc:`the ORM </topics/db/index>`. Ask on
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+ |django-users| or the `#django IRC channel
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+ <irc://irc.freenode.net/django>`_ to see if the ORM supports your use case.
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+
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.. warning::
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You should be very careful whenever you write raw SQL. Every time you use
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@@ -174,6 +187,9 @@ of people with their ages calculated by the database::
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Jane is 42.
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...
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+You can often avoid using raw SQL to compute annotations by instead using a
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+:ref:`Func() expression <func-expressions>`.
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+
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__ https://www.postgresql.org/docs/current/static/functions-datetime.html
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Passing parameters into ``raw()``
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