Enable Write-Ahead Logging (WAL) for SQLite to improve performance when using it.

photologue/apps.py

@@ -3,8 +3,25 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 from django.apps import AppConfig
+from django.db.backends.signals import connection_created
 
 
 class PhotologueConfig(AppConfig):
     default_auto_field = "django.db.models.AutoField"
     name = "photologue"
+
+    def ready(self):
+        from django.db import connection
+
+        def enable_sqlite_wal(sender, connection, **kwargs):
+            if connection.vendor == "sqlite":
+                cursor = connection.cursor()
+                cursor.execute("PRAGMA journal_mode=WAL;")
+                cursor.execute("PRAGMA synchronous=OFF;")
+                cursor.execute("PRAGMA journal_size_limit=67108864;")
+                cursor.execute("PRAGMA wal_autocheckpoint=1000;")
+                cursor.execute("PRAGMA cache_size=-65536;")
+                cursor.execute("PRAGMA temp_store=MEMORY;")
+                cursor.execute("PRAGMA mmap_size=268435456;")
+
+        connection_created.connect(enable_sqlite_wal)