fix: add command to delete persons with no distinct id's (#25657)

posthog/management/commands/delete_persons_with_no_distinct_ids.py

@@ -0,0 +1,70 @@
+from django.core.management.base import BaseCommand, CommandError
+from django.db import connection
+
+
+class Command(BaseCommand):
+    help = "Delete person rows that have no associated persondistinctid rows, by team"
+
+    def add_arguments(self, parser):
+        parser.add_argument("--team-id", default=None, type=int, help="Team ID to migrate from (on this instance)")
+        parser.add_argument("--dry-run", action="store_false", help="Dry run (default: true)")
+
+    def handle(self, **options):
+        team_id = options["team_id"]
+        dry_run = options["dry_run"]
+
+        if not team_id:
+            raise CommandError("source Team ID is required")
+
+        print("Deleting persons with no distinct ids for team", team_id)  # noqa: T201
+
+        if dry_run:
+            delete_persons_without_distinct_ids_raw_sql_dry_run(team_id)
+        else:
+            delete_persons_without_distinct_ids_raw_sql(team_id)
+
+
+def delete_persons_without_distinct_ids_raw_sql(team_id):
+    with connection.cursor() as cursor:
+        cursor.execute(
+            """
+            WITH persons_to_delete AS (
+                SELECT p.id
+                FROM posthog_person p
+                LEFT JOIN posthog_persondistinctid pd ON p.id = pd.person_id AND p.team_id = pd.team_id
+                WHERE p.team_id = %s AND pd.id IS NULL
+            )
+            DELETE FROM posthog_person
+            WHERE id IN (SELECT id FROM persons_to_delete)
+            RETURNING id;
+        """,
+            [team_id],
+        )
+
+        deleted_ids = cursor.fetchall()
+        deleted_count = len(deleted_ids)
+
+    print(f"Deleted {deleted_count} Person objects with no PersonDistinctIds for team {team_id}.")  # noqa: T201
+    return deleted_count
+
+
+def delete_persons_without_distinct_ids_raw_sql_dry_run(team_id):
+    with connection.cursor() as cursor:
+        cursor.execute(
+            """
+            WITH persons_to_delete AS (
+                SELECT p.id
+                FROM posthog_person p
+                LEFT JOIN posthog_persondistinctid pd ON p.id = pd.person_id AND p.team_id = pd.team_id
+                WHERE p.team_id = %s AND pd.id IS NULL
+            )
+            SELECT COUNT(*) FROM persons_to_delete;
+        """,
+            [team_id],
+        )
+
+        deleted_count = cursor.fetchone()
+        deleted_count = deleted_count[0] if deleted_count else 0
+
+    print(f"Would have deleted {deleted_count} Person objects with no PersonDistinctIds for team {team_id}.")  # noqa: T201
+    return deleted_count