diff --git a/kfet/migrations/0008_auto_20160804_1736.py b/kfet/migrations/0008_auto_20160804_1736.py
new file mode 100644
index 00000000..1abbb76a
--- /dev/null
+++ b/kfet/migrations/0008_auto_20160804_1736.py
@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+import django.core.validators
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0007_auto_20160804_0641'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='account',
+            name='trigramme',
+            field=models.CharField(unique=True, validators=[django.core.validators.RegexValidator(regex='^[^a-z]{3}$')], db_index=True, max_length=3),
+        ),
+    ]
diff --git a/kfet/models.py b/kfet/models.py
index af5ac686..ad51383a 100644
--- a/kfet/models.py
+++ b/kfet/models.py
@@ -21,7 +21,8 @@ class Account(models.Model):
     trigramme = models.CharField(
         unique     = True,
         max_length = 3,
-        validators = [RegexValidator(regex='^[^a-z]{3}$')])
+        validators = [RegexValidator(regex='^[^a-z]{3}$')],
+        db_index   = True)
     balance = models.DecimalField(
         max_digits = 6, decimal_places = 2,
         default = 0)