public function count($what=null, $group_by=null) {
		$r = $this->_function('COUNT', $what, $group_by);
		if(!is_array($r))
			$r = (int)$r;
		return $r;
	}
public function count($what=null, $group_by=null) {
		$r = $this->_function('COUNT', $what, $group_by);
		if(!is_array($r))
			$r = (int)$r;
		return $r;
	}
public function count ( $ what = null , $ group_by = null ) { $ r = $ this -> _function ( 'COUNT' , $ what , $ group_by ) ; if ( ! is_array ( $ r ) ) $ r = ( int ) $ r ; return $ r ; }
Count number of rows.
@param  string $what
@param  string $group_by
@return string
@api
Count number of rows .