Fixed #26709 -- Added class-based indexes.

Added the AddIndex and RemoveIndex operations to use them in migrations.

Thanks markush, mjtamlyn, timgraham, and charettes for review and advice.

4 files changed, 87 insertions, 0 deletions

diff --git a/docs/index.txt b/docs/index.txt
index 58044f574e..ab38fa02f9 100644
--- a/docs/index.txt
+++ b/docs/index.txt
@@ -82,6 +82,7 @@ manipulating the data of your Web application. Learn more about it below:
 * **Models:**
   :doc:`Introduction to models <topics/db/models>` |
   :doc:`Field types <ref/models/fields>` |
+  :doc:`Indexes <ref/models/indexes>` |
   :doc:`Meta options <ref/models/options>` |
   :doc:`Model class <ref/models/class>`
 
diff --git a/docs/ref/migration-operations.txt b/docs/ref/migration-operations.txt
index c8668d108e..485add5bcc 100644
--- a/docs/ref/migration-operations.txt
+++ b/docs/ref/migration-operations.txt
@@ -192,6 +192,43 @@ field like ``models.IntegerField()`` on most databases.
 Changes a field's name (and, unless :attr:`~django.db.models.Field.db_column`
 is set, its column name).
 
+``AddIndex``
+------------
+
+.. class:: AddIndex(model_name, index)
+
+.. versionadded:: 1.11
+
+Creates an index in the database table for the model with ``model_name``.
+``index`` is an instance of the :class:`~django.db.models.Index` class.
+
+For example, to add an index on the ``title`` and ``author`` fields of the
+``Book`` model::
+
+    from django.db import migrations, models
+
+    class Migration(migrations.Migration):
+        operations = [
+            migrations.AddIndex(
+                'Book',
+                models.Index(fields=['title', 'author'], name='my_index_name'),
+            ),
+        ]
+
+If you're writing your own migration to add an index, it's recommended to pass
+a ``name`` to the ``index`` as done above so that you can reference it if you
+later want to remove it. Otherwise, a name will be autogenerated and you'll
+have to inspect the database to find the index name if you want to remove it.
+
+``RemoveIndex``
+---------------
+
+.. class:: RemoveIndex(model_name, name)
+
+.. versionadded:: 1.11
+
+Removes the index named ``name`` from the model with ``model_name``.
+
 Special Operations
 ==================
 
diff --git a/docs/ref/models/index.txt b/docs/ref/models/index.txt
index 103775e269..d731ee37dc 100644
--- a/docs/ref/models/index.txt
+++ b/docs/ref/models/index.txt
@@ -8,6 +8,7 @@ Model API reference. For introductory material, see :doc:`/topics/db/models`.
    :maxdepth: 1
 
    fields
+   indexes
    meta
    relations
    class
diff --git a/docs/ref/models/indexes.txt b/docs/ref/models/indexes.txt
new file mode 100644
index 0000000000..c3c8d1b6eb
--- /dev/null
+++ b/docs/ref/models/indexes.txt
@@ -0,0 +1,48 @@
+=====================
+Model index reference
+=====================
+
+.. module:: django.db.models.indexes
+
+.. currentmodule:: django.db.models
+
+.. versionadded:: 1.11
+
+Index classes ease creating database indexes. This document explains the API
+references of :class:`Index` which includes the `index options`_.
+
+.. admonition:: Referencing built-in indexes
+
+    Indexes are defined in ``django.db.models.indexes``, but for convenience
+    they're imported into :mod:`django.db.models`. The standard convention is
+    to use ``from django.db import models`` and refer to the indexes as
+    ``models.<IndexClass>``.
+
+``Index`` options
+=================
+
+.. class:: Index(fields=[], name=None)
+
+    Creates an index (B-Tree) in the database.
+
+``fields``
+-----------
+
+.. attribute:: Index.fields
+
+A list of the name of the fields on which the index is desired.
+
+``name``
+--------
+
+.. attribute:: Index.name
+
+The name of the index. If ``name`` isn't provided Django will auto-generate a
+name. For compatibility with different databases, index names cannot be longer
+than 30 characters and shouldn't start with a number (0-9) or underscore (_).
+
+.. seealso::
+
+    Use the :class:`~django.db.migrations.operations.AddIndex` and
+    :class:`~django.db.migrations.operations.RemoveIndex` operations to add
+    and remove indexes.