function()
{
if (!$this->write) {
$r = [];
$ds = $this->_fetchAll(\PDO::FETCH_ASSOC);
foreach ($ds as $d){
foreach ($d as $k => $v){
if (!isset($r[$k])) {
$r[$k] = [];
}
$r[$k][] = $v;
}
}
return $r;
}
return null;
}
