reduce team shift view query count

shiftregister/app/migrations/0012_alter_shift_deleted_alter_shift_start_at.py

@@ -0,0 +1,23 @@
+# Generated by Django 4.0.4 on 2023-05-28 10:04
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("app", "0011_room_description"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="shift",
+            name="deleted",
+            field=models.BooleanField(db_index=True, default=False),
+        ),
+        migrations.AlterField(
+            model_name="shift",
+            name="start_at",
+            field=models.DateTimeField(db_index=True),
+        ),
+    ]

shiftregister/app/models.py

@@ -26,13 +26,13 @@ class Room(models.Model):
 
 class Shift(models.Model):
     room = models.ForeignKey(Room, on_delete=models.RESTRICT)
-    start_at = models.DateTimeField()
+    start_at = models.DateTimeField(db_index=True)
     duration = models.DurationField()
     required_helpers = models.IntegerField(
         default=0, help_text="When this is set to zero, the room value is used instead."
     )
     description = models.TextField(blank=True, default="")
-    deleted = models.BooleanField(default=False)
+    deleted = models.BooleanField(default=False, db_index=True)
 
     def with_reg_count():
         return Shift.objects.annotate(

shiftregister/team/views.py

@@ -93,7 +93,9 @@ def add_helper_shift(self):
 
 @login_required
 def shift_detail(request, pk):
-    shift = get_object_or_404(Shift, pk=pk)
+    shift = get_object_or_404(
+        Shift.with_reg_count().prefetch_related("shiftregistration_set__helper"), pk=pk
+    )
     form = HelperShift()
     if request.method == "POST":
         form = HelperShift(request.POST)