From bbb9c86ba444f49b9410d69e2ec8af8c11673a4a Mon Sep 17 00:00:00 2001
From: Trenton H <797416+stumpylog@users.noreply.github.com>
Date: Wed, 29 Jul 2026 07:14:13 -0700
Subject: [PATCH] Fix: avoid NotSupportedError from document_importer on
 MariaDB (#13400)

---
 .../management/commands/document_importer.py          | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/documents/management/commands/document_importer.py b/src/documents/management/commands/document_importer.py
index 90986858b..0e54b0ced 100644
--- a/src/documents/management/commands/document_importer.py
+++ b/src/documents/management/commands/document_importer.py
@@ -386,10 +386,19 @@ class Command(CryptMixin, PaperlessCommand):
                 raise DeserializationError(
                     f"{model.__name__} has no updatable fields; PK-only models are not supported by the importer",
                 )
+            # MySQL/MariaDB support upserts via ON DUPLICATE KEY UPDATE but,
+            # unlike PostgreSQL/SQLite, cannot target a specific unique field
+            # for the conflict -- passing unique_fields there raises
+            # NotSupportedError.
+            unique_fields = (
+                [model._meta.pk.attname]
+                if connection.features.supports_update_conflicts_with_target
+                else None
+            )
             model.objects.bulk_create(  # type: ignore[attr-defined]
                 instances,
                 update_conflicts=True,
-                unique_fields=[model._meta.pk.attname],
+                unique_fields=unique_fields,
                 update_fields=update_fields,
             )
             loaded_models.add(model)