private function _do_query( $query ) {
if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
$this->timer_start();
}

if ( ! empty( $this->dbh ) && $this->use_mysqli ) {
$this->result = mysqli_query( $this->dbh, $query );
} elseif ( ! empty( $this->dbh ) ) {
$this->result = mysql_query( $query, $this->dbh );
}
$this->num_queries++;

if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
$this->queries[] = array( $query, $this->timer_stop(), $this->get_caller() );
}
}