diff --git a/DataStorage/Database/Mapper/DataMapperAbstract.php b/DataStorage/Database/Mapper/DataMapperAbstract.php
index 8c09190af..7d53acb83 100644
--- a/DataStorage/Database/Mapper/DataMapperAbstract.php
+++ b/DataStorage/Database/Mapper/DataMapperAbstract.php
@@ -31,6 +31,8 @@ abstract class DataMapperAbstract
 
     protected int $type = 0;
 
+    protected int $depth = 1;
+
     protected array $with = [];
 
 	protected array $sort = [];
diff --git a/DataStorage/Database/Mapper/DataMapperFactory.php b/DataStorage/Database/Mapper/DataMapperFactory.php
index 79b2ee6af..cffd749a7 100644
--- a/DataStorage/Database/Mapper/DataMapperFactory.php
+++ b/DataStorage/Database/Mapper/DataMapperFactory.php
@@ -158,6 +158,13 @@ class DataMapperFactory
     {
     }
 
+    public static function db(ConnectionAbstract $db = null) : string
+    {
+        self::$db = $db;
+
+        return static::class;
+    }
+
     public static function reader(ConnectionAbstract $db = null) : ReadMapper
 	{
 		return new ReadMapper(new static(), $db ?? self::$db);
diff --git a/DataStorage/Database/Mapper/DeleteMapper.php b/DataStorage/Database/Mapper/DeleteMapper.php
index 2864c7661..23dfd3fdb 100644
--- a/DataStorage/Database/Mapper/DeleteMapper.php
+++ b/DataStorage/Database/Mapper/DeleteMapper.php
@@ -68,7 +68,7 @@ class DeleteMapper extends DataMapperAbstract
 
     private function deleteModel(object $obj, mixed $objId, \ReflectionClass $refClass = null) : void
     {
-        $query = new Builder(self::$db);
+        $query = new Builder($this->db);
         $query->delete()
             ->from($this->mapper::TABLE)
             ->where($this->mapper::TABLE . '.' . $this->mapper::PRIMARYFIELD, '=', $objId);
@@ -112,7 +112,7 @@ class DeleteMapper extends DataMapperAbstract
             }
         }
 
-        $sth = self::$db->con->prepare($query->toSql());
+        $sth = $this->db->con->prepare($query->toSql());
         if ($sth !== false) {
             $sth->execute();
         }
@@ -235,19 +235,19 @@ class DeleteMapper extends DataMapperAbstract
     {
         if (empty($objsIds)
             || $this->mapper::HAS_MANY[$propertyName]['table'] === $this->mapper::TABLE
-            || $this->mapper::HAS_MANY[$propertyName]['table'] === $this->mapper::HAS_MANY[$propertyName]['mapper']::$table
+            || $this->mapper::HAS_MANY[$propertyName]['table'] === $this->mapper::HAS_MANY[$propertyName]['mapper']::TABLE
         ) {
             return;
         }
 
         foreach ($objsIds as $src) {
-            $relQuery = new Builder(self::$db);
+            $relQuery = new Builder($this->db);
             $relQuery->delete()
                 ->from($this->mapper::HAS_MANY[$propertyName]['table'])
                 ->where($this->mapper::HAS_MANY[$propertyName]['table'] . '.' . $this->mapper::HAS_MANY[$propertyName]['external'], '=', $src)
                 ->where($this->mapper::HAS_MANY[$propertyName]['table'] . '.' . $this->mapper::HAS_MANY[$propertyName]['self'], '=', $objId, 'and');
 
-            $sth = self::$db->con->prepare($relQuery->toSql());
+            $sth = $this->db->con->prepare($relQuery->toSql());
             if ($sth !== false) {
                 $sth->execute();
             }
diff --git a/DataStorage/Database/Mapper/ReadMapper.php b/DataStorage/Database/Mapper/ReadMapper.php
index 1bf1e7bc7..8c6c61fca 100644
--- a/DataStorage/Database/Mapper/ReadMapper.php
+++ b/DataStorage/Database/Mapper/ReadMapper.php
@@ -27,7 +27,6 @@ use phpOMS\Utils\ArrayUtils;
  */
 class ReadMapper extends DataMapperAbstract
 {
-    private int $depth = 1;
     private $columns = [];
 
 	public function get() : self
diff --git a/DataStorage/Database/Mapper/UpdateMapper.php b/DataStorage/Database/Mapper/UpdateMapper.php
index 64c823f49..c6e10d329 100644
--- a/DataStorage/Database/Mapper/UpdateMapper.php
+++ b/DataStorage/Database/Mapper/UpdateMapper.php
@@ -81,7 +81,7 @@ class UpdateMapper extends DataMapperAbstract
             return;
         }
 
-        $query = new Builder(self::$db);
+        $query = new Builder($this->db);
         $query->update($this->mapper::TABLE)
             ->where($this->mapper::TABLE . '.' . $this->mapper::PRIMARYFIELD, '=', $objId);
 
@@ -140,7 +140,7 @@ class UpdateMapper extends DataMapperAbstract
         }
 
         try {
-            $sth = self::$db->con->prepare($query->toSql());
+            $sth = $this->db->con->prepare($query->toSql());
             if ($sth !== false) {
                 $sth->execute();
             }
@@ -236,13 +236,13 @@ class UpdateMapper extends DataMapperAbstract
 
                     $relMapper->execute($value);
 
-                    $objsIds[$propertyName][$key] = $value;
+                    $objsIds[$propertyName][$key] = $primaryKey;
 
                     continue;
                 }
 
                 // create if not existing
-                if ($this->mapper::HAS_MANY[$propertyName]['table'] === $this->mapper::HAS_MANY[$propertyName]['mapper']::$table
+                if ($this->mapper::HAS_MANY[$propertyName]['table'] === $this->mapper::HAS_MANY[$propertyName]['mapper']::TABLE
                     && isset($mapper::COLUMNS[$this->mapper::HAS_MANY[$propertyName]['self']])
                 ) {
                     $relProperty = $relReflectionClass->getProperty($mapper::COLUMNS[$this->mapper::HAS_MANY[$propertyName]['self']]['internal']);
@@ -291,15 +291,15 @@ class UpdateMapper extends DataMapperAbstract
             $sth->execute();
             $result =  $sth->fetchAll(\PDO::FETCH_COLUMN);
 
-            $removes = \array_diff($result, \array_keys($objsIds[$member] ?? []));
-            $adds    = \array_diff(\array_keys($objsIds[$member] ?? []), $result);
+            $removes = \array_diff($result, \array_values($objsIds[$member] ?? []));
+            $adds    = \array_diff(\array_values($objsIds[$member] ?? []), $result);
 
             if (!empty($removes)) {
-                $this->mapper::remover()->deleteRelationTable($member, $removes, $objId);
+                $this->mapper::remover(db: $this->db)->deleteRelationTable($member, $removes, $objId);
             }
 
             if (!empty($adds)) {
-                $this->mapper::writer()->createRelationTable($member, $adds, $objId);
+                $this->mapper::writer(db: $this->db)->createRelationTable($member, $adds, $objId);
             }
         }
     }
diff --git a/DataStorage/Database/Mapper/WriteMapper.php b/DataStorage/Database/Mapper/WriteMapper.php
index f05442e8e..b1d434f19 100644
--- a/DataStorage/Database/Mapper/WriteMapper.php
+++ b/DataStorage/Database/Mapper/WriteMapper.php
@@ -74,7 +74,7 @@ class WriteMapper extends DataMapperAbstract
 
     private function createModel(object $obj, \ReflectionClass $refClass) : mixed
     {
-        $query = new Builder(self::$db);
+        $query = new Builder($this->db);
         $query->into($this->mapper::TABLE);
 
         foreach ($this->mapper::COLUMNS as $column) {
@@ -128,7 +128,7 @@ class WriteMapper extends DataMapperAbstract
         }
 
         try {
-            $sth = self::$db->con->prepare($query->toSql());
+            $sth = $this->db->con->prepare($query->toSql());
             $sth->execute();
         } catch (\Throwable $t) {
             \var_dump($t->getMessage());
@@ -136,7 +136,7 @@ class WriteMapper extends DataMapperAbstract
             return -1;
         }
 
-        $objId = empty($id = $this->mapper::getObjectId($obj, $refClass)) ? self::$db->con->lastInsertId() : $id;
+        $objId = empty($id = $this->mapper::getObjectId($obj, $refClass)) ? $this->db->con->lastInsertId() : $id;
         \settype($objId, $this->mapper::COLUMNS[$this->mapper::PRIMARYFIELD]['type']);
 
         return $objId;
@@ -313,7 +313,7 @@ class WriteMapper extends DataMapperAbstract
             return;
         }
 
-        $relQuery = new Builder(self::$db);
+        $relQuery = new Builder($this->db);
         $relQuery->into($this->mapper::HAS_MANY[$propertyName]['table'])
             ->insert($this->mapper::HAS_MANY[$propertyName]['external'], $this->mapper::HAS_MANY[$propertyName]['self']);
 
@@ -331,7 +331,7 @@ class WriteMapper extends DataMapperAbstract
         }
 
         try {
-            $sth = self::$db->con->prepare($relQuery->toSql());
+            $sth = $this->db->con->prepare($relQuery->toSql());
             if ($sth !== false) {
                 $sth->execute();
             }
diff --git a/DataStorage/Database/Query/Builder.php b/DataStorage/Database/Query/Builder.php
index 647a002ba..375386528 100644
--- a/DataStorage/Database/Query/Builder.php
+++ b/DataStorage/Database/Query/Builder.php
@@ -690,7 +690,7 @@ class Builder extends BuilderAbstract
      */
     public function newest(string $column) : self
     {
-        $this->orderBy($column, 'DESC');
+        $this->orderBy($column, OrderType::DESC);
 
         return $this;
     }
@@ -706,7 +706,7 @@ class Builder extends BuilderAbstract
      */
     public function oldest(string $column) : self
     {
-        $this->orderBy($column, 'ASC');
+        $this->orderBy($column, OrderType::ASC);
 
         return $this;
     }
@@ -721,7 +721,7 @@ class Builder extends BuilderAbstract
      *
      * @since 1.0.0
      */
-    public function orderBy(string | array $columns, string | array $order = 'DESC') : self
+    public function orderBy(string | array $columns, string | array $order = OrderType::DESC) : self
     {
         if (\is_string($columns)) {
             $columns = [$columns];