77     function &
executeStoredProc($name, $params = null, $types = null, $result_class = 
true, $result_wrap_class = 
false)
 
   85             'method not implemented', __FUNCTION__);
 
  116     function now($type = 
'timestamp')
 
  120             return 'CURRENT_TIME';
 
  122             return 'CURRENT_DATE';
 
  125             return 'CURRENT_TIMESTAMP';
 
  138     function substring($value, $position = 1, $length = null)
 
  140         if (!is_null($length)) {
 
  141             return "SUBSTRING($value FROM $position FOR $length)";
 
  143         return "SUBSTRING($value FROM $position)";
 
  160         $args = func_get_args();
 
  161         return "(".implode(
' || ', $args).
")";
 
  190         return "LOWER($expression)";
 
  205         return "UPPER($expression)";
 
  225             'method not implemented', __FUNCTION__);