base: add a BRIN index on ResourceLog.timestamp (#88960)

passerelle/base/migrations/0031_log_timestamp_brin_index.py

@@ -0,0 +1,23 @@
+# Generated by Django 3.2.18 on 2024-04-02 11:18
+
+import django.contrib.postgres.indexes
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('base', '0030_resourcelog_base_resour_appname_298cbc_idx'),
+    ]
+
+    operations = [
+        migrations.RemoveIndex(
+            model_name='resourcelog',
+            name='base_resour_appname_298cbc_idx',
+        ),
+        migrations.AddIndex(
+            model_name='resourcelog',
+            index=django.contrib.postgres.indexes.BrinIndex(
+                fields=['timestamp'], name='base_resour_timesta_ca10d1_brin'
+            ),
+        ),
+    ]

passerelle/base/models.py

@@ -19,6 +19,7 @@ from django.conf import settings
 from django.contrib.contenttypes import fields
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.postgres.fields import ArrayField
+from django.contrib.postgres.indexes import BrinIndex
 from django.core.exceptions import PermissionDenied, ValidationError
 from django.core.files.base import ContentFile
 from django.db import connection, models, transaction
@@ -914,7 +915,7 @@ class ResourceLog(models.Model):
         ordering = ('id',)
         permissions = (('see_resourcelog', 'Can see resource logs'),)
         indexes = [
-            models.Index(fields=['appname', '-timestamp']),
+            BrinIndex(fields=['timestamp']),
         ]
 
     @property