From 9bd04efd056b3bf563254260380baffbfb8f0373 Mon Sep 17 00:00:00 2001
From: Karl Hobley <karlhobley10@gmail.com>
Date: Wed, 19 Aug 2015 12:15:40 +0100
Subject: [PATCH] Added index on AbstractImage.created_at

Fixes #1598

Speeds up image index/chooser when many images exist in the site
---
 .../migrations/0007_auto_20150819_0614.py     | 24 +++++++++++++++++++
 .../migrations/0008_image_created_at_index.py | 19 +++++++++++++++
 wagtail/wagtailimages/models.py               |  2 +-
 3 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 wagtail/tests/testapp/migrations/0007_auto_20150819_0614.py
 create mode 100644 wagtail/wagtailimages/migrations/0008_image_created_at_index.py

diff --git a/wagtail/tests/testapp/migrations/0007_auto_20150819_0614.py b/wagtail/tests/testapp/migrations/0007_auto_20150819_0614.py
new file mode 100644
index 0000000000..cdf17659a5
--- /dev/null
+++ b/wagtail/tests/testapp/migrations/0007_auto_20150819_0614.py
@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('tests', '0006_image_file_size'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='customimagewithadminformfields',
+            name='created_at',
+            field=models.DateTimeField(db_index=True, verbose_name='Created at', auto_now_add=True),
+        ),
+        migrations.AlterField(
+            model_name='customimagewithoutadminformfields',
+            name='created_at',
+            field=models.DateTimeField(db_index=True, verbose_name='Created at', auto_now_add=True),
+        ),
+    ]
diff --git a/wagtail/wagtailimages/migrations/0008_image_created_at_index.py b/wagtail/wagtailimages/migrations/0008_image_created_at_index.py
new file mode 100644
index 0000000000..23dda8c912
--- /dev/null
+++ b/wagtail/wagtailimages/migrations/0008_image_created_at_index.py
@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('wagtailimages', '0007_image_file_size'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='image',
+            name='created_at',
+            field=models.DateTimeField(db_index=True, verbose_name='Created at', auto_now_add=True),
+        ),
+    ]
diff --git a/wagtail/wagtailimages/models.py b/wagtail/wagtailimages/models.py
index 032a6cfff6..1439d5563a 100644
--- a/wagtail/wagtailimages/models.py
+++ b/wagtail/wagtailimages/models.py
@@ -63,7 +63,7 @@ class AbstractImage(models.Model, TagSearchable):
     file = models.ImageField(verbose_name=_('File'), upload_to=get_upload_to, width_field='width', height_field='height')
     width = models.IntegerField(verbose_name=_('Width'), editable=False)
     height = models.IntegerField(verbose_name=_('Height'), editable=False)
-    created_at = models.DateTimeField(verbose_name=_('Created at'), auto_now_add=True)
+    created_at = models.DateTimeField(verbose_name=_('Created at'), auto_now_add=True, db_index=True)
     uploaded_by_user = models.ForeignKey(settings.AUTH_USER_MODEL, verbose_name=_('Uploaded by user'), null=True, blank=True, editable=False)
 
     tags = TaggableManager(help_text=None, blank=True, verbose_name=_('Tags'))