diff --git a/database/migrations/2026_03_06_163831_alter_position_authority_logs_nullable_user_position_id.php b/database/migrations/2026_03_06_163831_alter_position_authority_logs_nullable_user_position_id.php
new file mode 100644
index 0000000..6f54a74
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+++ b/database/migrations/2026_03_06_163831_alter_position_authority_logs_nullable_user_position_id.php
@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * 文件功能：将 position_authority_logs.user_position_id 改为可空
+ *
+ * 原字段为 NOT NULL，但超级管理员（id=1）无职务记录，
+ * 发放奖励时 user_position_id 为 null，导致约束违反错误。
+ * 修改为 nullable 后，超管操作写 null，普通职务人员写实际职务 ID。
+ *
+ * @author  ChatRoom Laravel
+ *
+ * @version 1.0.0
+ */
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * 将 user_position_id 改为可空，兼容超级管理员无职务的情况
+     */
+    public function up(): void
+    {
+        Schema::table('position_authority_logs', function (Blueprint $table) {
+            // 先删除原外键约束，再重新定义为 nullable
+            $table->dropForeign(['user_position_id']);
+
+            $table->unsignedBigInteger('user_position_id')
+                ->nullable()
+                ->change();
+
+            $table->foreign('user_position_id')
+                ->references('id')
+                ->on('user_positions')
+                ->nullOnDelete();
+        });
+    }
+
+    /**
+     * 回滚：恢复为 NOT NULL（需确保数据中无 null 值）
+     */
+    public function down(): void
+    {
+        Schema::table('position_authority_logs', function (Blueprint $table) {
+            $table->dropForeign(['user_position_id']);
+
+            $table->unsignedBigInteger('user_position_id')
+                ->nullable(false)
+                ->change();
+
+            $table->foreign('user_position_id')
+                ->references('id')
+                ->on('user_positions')
+                ->cascadeOnDelete();
+        });
+    }
+};