fix slow query

activities/migrations/0029_post_url_db_index.py

@@ -0,0 +1,17 @@
+from django.contrib.postgres.operations import AddIndexConcurrently
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    atomic = False
+
+    dependencies = [
+        ("activities", "0028_previewcard_post_preview_card"),
+    ]
+
+    operations = [
+        AddIndexConcurrently(
+            model_name="post",
+            index=models.Index(fields=["url"], name="activities_post_url_idx"),
+        ),
+    ]

activities/models/post.py

@@ -518,6 +518,7 @@ class Meta:
                 fields=["visibility", "local", "created"],
                 name="ix_post_local_public_created",
             ),
+            models.Index(fields=["url"], name="activities_post_url_idx"),
         ]
 
     class urls(urlman.Urls):

api/views/statuses.py

@@ -2,7 +2,6 @@
 from datetime import timedelta
 from typing import Literal
 
-from django.db.models import Q
 from django.http import HttpRequest
 from api.views import get_object_or_404
 from django.utils import timezone
@@ -123,12 +122,12 @@ def _extract_quote_from_trailing_url(
     if not match:
         return None, text
     url = match.group(2)
-    post = (
-        Post.objects.not_hidden()
-        .visible_to(identity, include_replies=True)
-        .filter(Q(object_uri=url) | Q(url=url))
-        .first()
-    )
+    # Look up by object_uri first (unique index), then fall back to url.
+    # Avoids an OR query that causes a full table scan on large tables.
+    base_qs = Post.objects.not_hidden().visible_to(identity, include_replies=True)
+    post = base_qs.filter(object_uri=url).first()
+    if post is None:
+        post = base_qs.filter(url=url).first()
     if not post:
         return None, text
     cleaned = text[: match.start(2)].rstrip("\n ")