Improve performance of global order search

src/pretix/base/migrations/0079_auto_20180115_0855.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.8 on 2018-01-15 08:55
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+from django.db.models import F
+from django.db.models.functions import Concat
+
+
+def set_full_invoice_no(app, schema_editor):
+    Invoice = app.get_model('pretixbase', 'Invoice')
+    Invoice.objects.all().update(
+        full_invoice_no=Concat(F('prefix'), F('invoice_no'))
+    )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0078_auto_20171206_1603'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='invoice',
+            name='full_invoice_no',
+            field=models.CharField(db_index=True, default='', max_length=190),
+            preserve_default=False,
+        ),
+        migrations.AlterField(
+            model_name='question',
+            name='type',
+            field=models.CharField(choices=[('N', 'Number'), ('S', 'Text (one line)'), ('T', 'Multiline text'), ('B', 'Yes/No'), ('C', 'Choose one from a list'), ('M', 'Choose multiple from a list'), ('F', 'File upload'), ('D', 'Date'), ('H', 'Time'), ('W', 'Date and time')], max_length=5, verbose_name='Question type'),
+        ),
+        migrations.RunPython(
+            set_full_invoice_no,
+            migrations.RunPython.noop
+        )
+    ]