diff --git a/dblayer.php b/dblayer.php
index 3dc902f..da88f83 100644
--- a/dblayer.php
+++ b/dblayer.php
@@ -171,8 +171,16 @@ class dblayer extends PDO
   }
 
   /** Create a new entry in the table. Datas must be an indexed array
-      @param array $datas Datas to be recorded (column=>value)*/
+      @param array $datas Datas to be recorded (column=>value)
+      @obsolete 0.5 */
   public function create ($datas)
+  {
+    return $this->insert ($datas);
+  }
+
+  /** Insert a new line of datas in the table. Datas must be an indexed array
+      @param array $datas Datas to be recorded (column=>value)*/
+  public function insert ($datas)
   {
     if ($this->db === null)
       throw new Exception (_("Database not connected"), 500);
@@ -237,8 +245,37 @@ class dblayer extends PDO
       }
     }
 
-    // TODO : Check if the foreign keys constrains are valid before doing the
-    // insertion
+    // Check if the foreign keys constrains are valid before doing the insertion
+    foreach ($this->foreign as $foreign=>$data)
+    {
+      $table = $data[0];
+      $column = $data[1];
+      $req = "SELECT $column FROM `$table` WHERE $column=:$column";
+      if ($this->debug) echo "DEBUG : $req\n";
+      $st = $this->db->prepare ($req);
+      $val = $datasOK[$foreign];
+      $key = $column;
+      if ($this->debug) echo "DEBUG BIND : $column->".var_export ($val, TRUE).
+                             "\n";
+      if ($val === null)
+        $st->bindValue (":$key", $val, PDO::PARAM_NULL);
+      elseif ($this->fields[$key][0] === "integer")
+        $st->bindValue (":$key", $val, PDO::PARAM_INT);
+      elseif ($this->fields[$key][0] === "varchar")
+        $st->bindValue (":$key", $val, PDO::PARAM_STR);
+      elseif ($this->fields[$key][0] === "datetime")
+        $st->bindValue (":$key", $val, PDO::PARAM_STR);
+      else
+        throw new Exception ("TO BE DEVELOPPED : ".$this->fields[$key][0], 500);
+      $st->execute ();
+      $res = array ();
+      while ($d = $st->fetch (PDO::FETCH_ASSOC))
+        $res[] = $d;
+      if (count ($res) === 0)
+        throw new Exception (sprintf (_("The foreign key '%s' doesn't exists"),
+                                      $column), 405);
+    }
+
     $req = "INSERT INTO `".$this->table."` ";
     $req .= "(".implode (",", array_keys ($datasOK)).")";
     $req .= " VALUES ";
@@ -430,7 +467,37 @@ class dblayer extends PDO
       }
     }
 
-    // TODO : Check if the foreign keys constrains are valid before doing the
+    // Check if the foreign keys constrains are valid before doing the update
+    foreach ($this->foreign as $foreign=>$data)
+    {
+      $table = $data[0];
+      $column = $data[1];
+      $req = "SELECT $column FROM `$table` WHERE $column=:$column";
+      if ($this->debug) echo "DEBUG : $req\n";
+      $st = $this->db->prepare ($req);
+      $val = $datasOK[$foreign];
+      $key = $column;
+      if ($this->debug) echo "DEBUG BIND : $column->".var_export ($val, TRUE).
+                             "\n";
+      if ($val === null)
+        $st->bindValue (":$key", $val, PDO::PARAM_NULL);
+      elseif ($this->fields[$key][0] === "integer")
+        $st->bindValue (":$key", $val, PDO::PARAM_INT);
+      elseif ($this->fields[$key][0] === "varchar")
+        $st->bindValue (":$key", $val, PDO::PARAM_STR);
+      elseif ($this->fields[$key][0] === "datetime")
+        $st->bindValue (":$key", $val, PDO::PARAM_STR);
+      else
+        throw new Exception ("TO BE DEVELOPPED : ".$this->fields[$key][0], 500);
+      $st->execute ();
+      $res = array ();
+      while ($d = $st->fetch (PDO::FETCH_ASSOC))
+        $res[] = $d;
+      if (count ($res) === 0)
+        throw new Exception (sprintf (_("The foreign key '%s' doesn't exists"),
+                                      $column), 405);
+    }
+
     $datasOK[$this->primary] = $updatekey;
     $req = "UPDATE `".$this->table."` SET ";
     $i = 0;