diff --git a/Base/Model.php b/Base/Model.php
index c0501be..0e7945b 100644
--- a/Base/Model.php
+++ b/Base/Model.php
@@ -49,7 +49,7 @@ abstract class Model extends Component implements ModelInterface, ArrayAccess, \
 
 
     /** @var null|string */
-    protected ?string $primary = NULL;
+    protected string $primary = '';
 
 
     /**
@@ -187,17 +187,17 @@ abstract class Model extends Component implements ModelInterface, ArrayAccess, \
      */
     public function hasPrimary(): bool
     {
-        return !empty($this->primary);
+        return $this->primary != '';
     }
 
     /**
      * @return null|string
      * @throws
      */
-    public function getPrimary(): ?string
+    public function getPrimary(): string
     {
         if (!$this->hasPrimary()) {
-            return NULL;
+            return '';
         }
         return $this->primary;
     }
@@ -222,10 +222,11 @@ abstract class Model extends Component implements ModelInterface, ArrayAccess, \
      */
     public function getPrimaryValue(): ?int
     {
-        if (!$this->hasPrimary()) {
+        if ($this->hasPrimary()) {
+            return (int)$this->_oldAttributes[$this->getPrimary()] ?? null;
+        } else {
             return null;
         }
-        return $this->_oldAttributes[$this->getPrimary()] ?? null;
     }
 
     /**