diff --git a/library/think/Model.php b/library/think/Model.php
index 92b49037..31caed62 100644
--- a/library/think/Model.php
+++ b/library/think/Model.php
@@ -586,7 +586,8 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
             }
 
             $result = $this->db()->where($where)->update($data);
-
+            // 清空change
+            $this->change = [];
             // 更新回调
             $this->trigger('after_update', $this);
         } else {
@@ -613,16 +614,14 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
                 }
                 $result = $insertId;
             }
+            // 标记为更新
+            $this->isUpdate = true;            
             // 新增回调
             $this->trigger('after_insert', $this);
         }
         // 写入回调
         $this->trigger('after_write', $this);
-
-        // 标记为更新
-        $this->isUpdate = true;
-        // 清空change
-        $this->change = [];
+        
         return $result;
     }
 
diff --git a/library/think/model/Merge.php b/library/think/model/Merge.php
index 3da4fc07..69ef91c5 100644
--- a/library/think/model/Merge.php
+++ b/library/think/model/Merge.php
@@ -183,10 +183,21 @@ class Merge extends Model
                     return false;
                 }
 
+                if (empty($where) && !empty($this->updateWhere)) {
+                    $where = $this->updateWhere;
+                }
+
+                if (!empty($where)) {
+                    $pk = $this->getPk();
+                    if (is_string($pk) && isset($data[$pk])) {
+                        unset($data[$pk]);
+                    }
+                }
+                          
                 // 处理模型数据
                 $data = $this->parseData($this->name, $this->data);
                 // 写入主表数据
-                $result = $db->strict(false)->update($data);
+                $result = $db->strict(false)->where($where)->update($data);
 
                 // 写入附表数据
                 foreach (static::$relationModel as $key => $model) {