如何最大限度地减少查询

Question

我有2个表wttt将需要4个元组上升或插入，例如 表将有一个游戏和每个球员职业生涯的条目（2）SO是4元组。关于我的头顶，我只能想到，如果不存在，则为player1和game执行SELECT插入else更新，为player1和职业提供.......这看起来像很多数据库查询是否存在更好的方式来处理这个？在PHP MYSQL PDO现有代码：

CREATE TABLE `standings` ( 
`id` int(11) NOT NULL AUTO_INCREMENT, 
`league_id` int(11) NOT NULL, 
`season_id` int(11) NOT NULL, 
`team_id` int(11) NOT NULL, 
`statistic_type_id` int(11) NOT NULL, 
`wlt` varchar(30) NOT NULL);  


$sth = $dbh->prepare('Select * from standings 
      where league_id=? and season_id=? and team_id=? and statistic_type_id=$? '); 

$data = $sth->execute(array($l, $s, $t, $st)); 

$data = $sth->fetchAll(); 

if ($sth->rowCount() == 0) {  
    $wlt = $w . '," . $lo . ',' . $di; 
    $sth = $dbh->prepare('INSERT INTO standings (id, league_id, season_id,  
       team_id, statistic_type_id, wlt) 
       VALUES(0, ?, ?, ?, ?, ?); 

     $data = $sth->execute(array($l, $s, $t, $st, $wlt)); 

} else { 
    foreach ($data as $row) { 
     $wlt = explode(",", $row['wlt']); 
     $wlt[0] = $wlt[0] + $w; 
     $wlt[1] = $wlt[1] + $lo;  
     $wlt[2] = $wlt[2] + $di; 
     $nwlt = implode(",", $wlt); 

     $sth = $dbh->prepare('UPDATE standings SET wlt=? 
      where league_id=? and season_id=? and team_id=? and statistic_type_id=$? '); 

     $data = $sth->execute(array($nwlt, $l, $s, $t, $st)); 
    } 
} 

Answer 1

您可以使用更换成http://dev.mysql.com/doc/refman/5.0/en/replace.html