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-rw-r--r--docs/ref/models/expressions.txt22
1 files changed, 22 insertions, 0 deletions
diff --git a/docs/ref/models/expressions.txt b/docs/ref/models/expressions.txt
index 9d85442d9c..67baef7dfc 100644
--- a/docs/ref/models/expressions.txt
+++ b/docs/ref/models/expressions.txt
@@ -183,6 +183,28 @@ the field value of each one, and saving each one back to the database::
* getting the database, rather than Python, to do work
* reducing the number of queries some operations require
+.. _slicing-using-f:
+
+Slicing ``F()`` expressions
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. versionadded:: 5.1
+
+For string-based fields, text-based fields, and
+:class:`~django.contrib.postgres.fields.ArrayField`, you can use Python's
+array-slicing syntax. The indices are 0-based and the ``step`` argument to
+``slice`` is not supported. For example:
+
+.. code-block:: pycon
+
+ >>> # Replacing a name with a substring of itself.
+ >>> writer = Writers.objects.get(name="Priyansh")
+ >>> writer.name = F("name")[1:5]
+ >>> writer.save()
+ >>> writer.refresh_from_db()
+ >>> writer.name
+ 'riya'
+
.. _avoiding-race-conditions-using-f:
Avoiding race conditions using ``F()``