1 files changed, 6 insertions, 0 deletions
diff --git a/src/datasets/array.php b/src/datasets/array.php
index 3340cd0..ee7f0df 100644
--- a/src/datasets/array.php
+++ b/src/datasets/array.php
@@ -44,10 +44,16 @@ class ezcGraphArrayDataSet extends ezcGraphDataSet
             throw new ezcGraphInvalidArrayDataSourceException( $data );
         }
 
+        $this->data = array();
         foreach ( $data as $key => $value )
         {
             $this->data[$key] = $value;
         }
+
+        if ( !count( $this->data ) )
+        {
+            throw new ezcGraphInvalidDataException( 'Data sets should contain some values.' );
+        }
     }
 
     /**