From 49ecbfa17ca543cc81f0f27359a0171a4d977e81 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mathias=20Gla=CC=88ser?= <mathias.glaeser@beaufort.ch>
Date: Tue, 8 Sep 2026 09:38:46 +0200
Subject: [PATCH] NULL-Chargennummer beim Speichern korrekt behandeln

---
 modules/erp/lager/service.php | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/modules/erp/lager/service.php b/modules/erp/lager/service.php
index ce1af83..2cc3bdc 100644
--- a/modules/erp/lager/service.php
+++ b/modules/erp/lager/service.php
@@ -365,7 +365,9 @@ function update_stock_lot_traceability(
             throw new InvalidArgumentException('Korrekturen und Abgaenge koennen nur auf der aktiven Charge gebucht werden');
         }
 
-        $lotNumberAssignment = $clearLotNumber ? 'NULL' : 'COALESCE(:lot_number, lot_number)';
+        $lotNumberAssignment = $clearLotNumber
+            ? 'NULL'
+            : ($lotNumber === null ? 'lot_number' : 'COALESCE(:lot_number, lot_number)');
         $updateStmt = $pdo->prepare(
             "UPDATE stock_lot
              SET lot_number = {$lotNumberAssignment},
@@ -385,7 +387,7 @@ function update_stock_lot_traceability(
             ':purchase_date' => $dates['purchase_date'],
             ':id' => $lotId,
         ];
-        if (!$clearLotNumber) {
+        if (!$clearLotNumber && $lotNumber !== null) {
             $updateParams[':lot_number'] = $lotNumber;
         }
         $updateStmt->execute($updateParams);