diff --git a/backend/app/Model/Order.php b/backend/app/Model/Order.php
index de1dc0e..00a888c 100644
--- a/backend/app/Model/Order.php
+++ b/backend/app/Model/Order.php
@@ -4,7 +4,7 @@ declare(strict_types=1);
 
 namespace App\Model;
 
-use Hyperf\DbConnection\Model\Model;
+use App\Model\OrderItem;
 
 /**
  * @property int $id 主键
@@ -58,13 +58,19 @@ class Order extends Model
      */
     protected array $casts = ['id' => 'integer', 'company_id' => 'integer', 'platform_id' => 'integer', 'store_id' => 'integer', 'order_status_id' => 'integer', 'payment_method_id' => 'integer', 'presale' => 'boolean', 'order_type_id' => 'integer', 'created_at' => 'datetime', 'updated_at' => 'datetime'];
 
-
     /**
-     * Get the order items for the order.
+     * 获取订单子项（基于 hypertable 分区键查询）
+     *
+     * @return \Hyperf\Database\Model\Collection
      */
-    public function items()
+    public function getOrderItems()
     {
-        return $this->hasMany(OrderItem::class, 'order_id', 'id');
+        return OrderItem::query()
+            ->where('platform_id', $this->platform_id)
+            ->where('store_id', $this->store_id)
+            ->where('platform_order_id', $this->platform_order_id)
+            ->where('created_date', $this->created_date)
+            ->get();
     }
 }
 
diff --git a/backend/app/Model/OrderItem.php b/backend/app/Model/OrderItem.php
index 891bab9..76d90a8 100644
--- a/backend/app/Model/OrderItem.php
+++ b/backend/app/Model/OrderItem.php
@@ -4,8 +4,6 @@ declare(strict_types=1);
 
 namespace App\Model;
 
-use Hyperf\DbConnection\Model\Model;
-
 /**
  * @property int $id 主键
  * @property int $company_id 公司 ID 与 Tools 保持一致
@@ -23,9 +21,10 @@ use Hyperf\DbConnection\Model\Model;
  * @property int $quantity 商品子项总数量
  * @property string $discount 订单子项总的折扣金额
  * @property string $total 总金额 = 单价X数量 - 折扣
+ * @property string $created_date 订单创建时间（与父订单 created_date 一致，hypertable 分区键）
  * @property string $ext 扩展字段
- * @property \Carbon\Carbon $created_at 
- * @property \Carbon\Carbon $updated_at 
+ * @property \Carbon\Carbon $created_at
+ * @property \Carbon\Carbon $updated_at
  * @mixin \App_Model_OrderItem
  */
 class OrderItem extends Model
@@ -38,7 +37,7 @@ class OrderItem extends Model
     /**
      * The attributes that are mass assignable.
      */
-    protected array $fillable = ['id', 'company_id', 'platform_id', 'store_id', 'order_id', 'platform_order_id', 'sub_order_id', 'sub_order_type_id', 'product_id', 'platform_product_id', 'product_sku', 'product_barcode', 'unit_price', 'quantity', 'discount', 'total', 'ext', 'created_at', 'updated_at'];
+    protected array $fillable = ['id', 'company_id', 'platform_id', 'store_id', 'order_id', 'platform_order_id', 'sub_order_id', 'sub_order_type_id', 'product_id', 'platform_product_id', 'product_sku', 'product_barcode', 'unit_price', 'quantity', 'discount', 'total', 'created_date', 'ext', 'created_at', 'updated_at'];
 
     /**
      * The attributes that should be cast to native types.
@@ -46,10 +45,17 @@ class OrderItem extends Model
     protected array $casts = ['id' => 'integer', 'company_id' => 'integer', 'platform_id' => 'integer', 'store_id' => 'integer', 'order_id' => 'integer', 'sub_order_type_id' => 'integer', 'product_id' => 'integer', 'quantity' => 'integer', 'created_at' => 'datetime', 'updated_at' => 'datetime'];
 
     /**
-     * Get the order that owns the order item.
+     * 获取父订单（基于 hypertable 分区键查询）
+     *
+     * @return Order|null
      */
-    public function order()
+    public function getParentOrder(): ?Order
     {
-        return $this->belongsTo(Order::class, 'order_id', 'id');
+        return Order::query()
+            ->where('platform_id', $this->platform_id)
+            ->where('store_id', $this->store_id)
+            ->where('platform_order_id', $this->platform_order_id)
+            ->where('created_date', $this->created_date)
+            ->first();
     }
 }