diff --git a/core/migrations/0031_auto_20190906_1615.py b/core/migrations/0031_auto_20190906_1615.py
new file mode 100644
index 00000000..3c962332
--- /dev/null
+++ b/core/migrations/0031_auto_20190906_1615.py
@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.24 on 2019-09-06 14:15
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [("core", "0030_auto_20190704_1500")]
+
+    operations = [
+        migrations.AlterField(
+            model_name="sithfile",
+            name="is_folder",
+            field=models.BooleanField(
+                db_index=True, default=True, verbose_name="is folder"
+            ),
+        ),
+        migrations.AlterField(
+            model_name="sithfile",
+            name="is_in_sas",
+            field=models.BooleanField(
+                db_index=True, default=False, verbose_name="is in the SAS"
+            ),
+        ),
+    ]
diff --git a/core/models.py b/core/models.py
index b1def45c..f873e785 100644
--- a/core/models.py
+++ b/core/models.py
@@ -807,7 +807,7 @@ class SithFile(models.Model):
     view_groups = models.ManyToManyField(
         Group, related_name="viewable_files", verbose_name=_("view group"), blank=True
     )
-    is_folder = models.BooleanField(_("is folder"), default=True)
+    is_folder = models.BooleanField(_("is folder"), default=True, db_index=True)
     mime_type = models.CharField(_("mime type"), max_length=30)
     size = models.IntegerField(_("size"), default=0)
     date = models.DateTimeField(_("date"), default=timezone.now)
@@ -821,7 +821,7 @@ class SithFile(models.Model):
     )
     asked_for_removal = models.BooleanField(_("asked for removal"), default=False)
     is_in_sas = models.BooleanField(
-        _("is in the SAS"), default=False
+        _("is in the SAS"), default=False, db_index=True
     )  # Allows to query this flag, updated at each call to save()
 
     class Meta: