diff --git a/dblayeroo.php b/dblayeroo.php
index 5640a43..e929a29 100644
--- a/dblayeroo.php
+++ b/dblayeroo.php
@@ -1882,10 +1882,10 @@ class dblayeroo
     if ($this->table === null)
       $this->DBException (dgettext ("domframework",
                             "No table name defined to insert in the table"));
-    if ($this->unique === null)
+    if ($this->unique === null && $this->primary === null)
       $this->DBException (dgettext ("domframework",
                            "Unique fields of table are not defined"));
-    if (! is_array ($this->unique))
+    if (! is_array ($this->unique) && $this->unique !== null)
       $this->DBException (dgettext ("domframework",
                            "The unique configuration is not an array"));
     switch ($this->command)