diff --git a/composer.json b/composer.json
index b814b02..6cdaea9 100644
--- a/composer.json
+++ b/composer.json
@@ -7,6 +7,10 @@
         {
             "name": "Daniel Szakal",
             "email": "dszakal89@icloud.com"
+        },
+        {
+            "name": "Salvatore Campanella",
+            "email": "salvo.sav@gmail.com"
         }
     ],
     "require": {
diff --git a/src/AutoDb.php b/src/AutoDb.php
index 18c6583..1543b08 100644
--- a/src/AutoDb.php
+++ b/src/AutoDb.php
@@ -50,6 +50,15 @@ protected function __construct($sqlResource, $redisInstance = null, $connectionI
         $this->_connectionIdent = $connectionIdent;
     }
 
+    public function __sleep()
+    {
+        // Exclude the _sqlResource property from serialization
+        $properties = get_object_vars($this);
+        unset($properties['_sqlResource']);
+
+        return array_keys($properties);
+    }
+
     /**
      *
      * @param mysqli $sqlResource - one MySQL connection <-> One AutoDb instance
diff --git a/src/AutoRecord.php b/src/AutoRecord.php
index 5c1f434..f23cf1b 100644
--- a/src/AutoRecord.php
+++ b/src/AutoRecord.php
@@ -76,6 +76,15 @@ protected function __construct(AutoDb $autoDb, $table, $columnRules, $sqlResourc
         $this->_primaryKey = $columnRules['__primarykey'];
     }
 
+    public function __sleep()
+    {
+        // Exclude the _sqlResource property from serialization
+        $properties = get_object_vars($this);
+        unset($properties['_sqlResource']);
+
+        return array_keys($properties);
+    }
+
     private function initAttrsEmpty() {
         foreach ($this->_columnRules as $key => $value) {
             $this->_attributes[$key] = null;