/**
  * @see parent::getSpec()
  */
 function getSpec()
 {
     $spec = parent::getSpec();
     $spec->table = "ex_list";
     $spec->key = "ex_list_id";
     $spec->uniques["name"] = array("name");
     return $spec;
 }
 /**
  * @see parent::getSpec()
  */
 function getSpec()
 {
     $spec = parent::getSpec();
     $spec->table = "ex_class_field";
     $spec->key = "ex_class_field_id";
     $spec->uniques["name"] = array("ex_group_id", "name");
     // should ignore empty values
     //$spec->uniques["coord_label"] = array("ex_group_id", "coord_label_x", "coord_label_y");
     //$spec->uniques["coord_field"] = array("ex_group_id", "coord_field_x", "coord_field_y");
     return $spec;
 }