Question

我正在尝试学习如何将查询转换为PDO。我终于得到了一个简单的行（计数）查询，现在我正在处理更复杂的查询。

我目前正在使用以下查询。（对不起，它太复杂了;我还在努力简化它。）

$SeaURL = str_replace('Washington/', '', $MyURL);

$res = mysql_query ("SELECT P.URL, P.Title, P.Subtitle, P.MetaTitle, P.MetaDesc, P.KW, P.Live, PB.Common, PB.First, PB.Middle, PB.Last, PB.Prefix, PB.Suffix, PB.Born, PB.Died, PB.Birth_Place, PB.Death_Place, PB.Nationality, Brf.Site, Brf.Brief, PC.Class, PX.Article PXA, PX.Pagedex PXP, IVR.Article IVRA, IVR.Pagedex IVRP, SM.Article SMA, SM.Pagedex SMP
 FROM people P
 LEFT JOIN people_1_bio PB ON PB.URL = P.URL
 LEFT JOIN people_1_class PC ON PC.URL = P.URL
 LEFT JOIN people_briefs Brf ON Brf.URL = P.URL
 LEFT JOIN people_articles_px PX ON PX.URL = P.URL
 LEFT JOIN people_articles_ivr IVR ON IVR.URL = P.URL
 LEFT JOIN people_articles_sm SM ON SM.URL = P.URL
 WHERE P.URL LIKE '$MyURL' AND P.Site = '$MySiteID'
 GROUP BY Class") or die (mysql_error());

使用这个特定的查询，我需要一个while循环来定义一些值，其中一些我进一步放入数组（例如$ ClassList和$ ClassLinked）。

while ($row = mysql_fetch_array ($res))
{
 $URL = $row['URL'];
 $Title = $row['Title'];
 $Class = $row['Class'];
 $ClassList[] = $row['Class'];
 $ClassL = str_replace(' ', '_', $Class);
 $ClassLinked[] = '<a href="/People/'.$ClassL.'" title="'.$Class.'">'.$row['Class'].'</a>';
}

通过上述数据，我可以显示页面标题（例如$ Title = Carl Sagan）和他所属的类列表（数组）（例如$ ClassList [] =科学家|作家|政治活动家）。

这是我的PDO改造：

$dsn = "mysql:host=localhost;dbname=DATABASE;charset=utf8";
$opt = array(
    PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC
);
$pdo = new PDO($dsn,'USERNAME','PASSWORD', $opt);

$SeaURL = str_replace('Washington/', '', $MyURL);

$stm = $pdo->prepare("SELECT P.URL, P.Title, P.Subtitle, P.MetaTitle, P.MetaDesc, P.KW, P.Live, PB.Common, PB.First, PB.Middle, PB.Last, PB.Prefix, PB.Suffix, PB.Born, PB.Died, PB.Birth_Place, PB.Death_Place, PB.Nationality, Brf.Site, Brf.Brief, PC.Class, PX.Article PXA, PX.Pagedex PXP, IVR.Article IVRA, IVR.Pagedex IVRP, SM.Article SMA, SM.Pagedex SMP
 FROM people P
 LEFT JOIN people_1_bio PB ON PB.URL = P.URL
 LEFT JOIN people_1_class PC ON PC.URL = P.URL
 LEFT JOIN people_briefs Brf ON Brf.URL = P.URL
 LEFT JOIN people_articles_px PX ON PX.URL = P.URL
 LEFT JOIN people_articles_ivr IVR ON IVR.URL = P.URL
 LEFT JOIN people_articles_sm SM ON SM.URL = P.URL
 WHERE P.URL LIKE '$MyURL' AND P.Site = '$MySiteID'
 GROUP BY Class");
$stm->execute();
$data = $stm->fetchAll();

我认为我的查询不起作用，但是当我不知道如何显示结果时很难检查它。这就是我在这里问的问题。

如果我正确理解了教程@ https://stackoverflow.com/tags/pdo/info，fetchAll（）函数会替换while循环，对吗？

我的原始代码定义了以下值，然后我可以在单独的文件中回显：

$Class = $row['Class'];
$ClassList[] = $row['Class'];

使用我的新PDO脚本定义$ Class和$ ClassList的最佳方法是什么？

页面@ https://stackoverflow.com/tags/pdo/info使用foreach函数提供了一个非常混乱（且不完整？）的示例......

?>
<table>
<? foreach ($data as $row): ?>
  <tr>
    <td>
      <a href="news.php?<?=$row['id']?>">
        <?=htmlspecialchars($row['name'])?>
      </a>
    </td>
  </tr>
<? endforeach ?>

但我不打算在表格中显示所有数据。我如何将$ Class定义为单个值，将$ ClassList定义为一系列值（数组）？

Answer 1

使用PDOStatement fetch功能。在您的PDO改造代码中，删除行

$data = $stm->fetchAll();

使用

while( $row = $stm->fetch(PDO::FETCH_ASSOC ) {

而是在循环的开头处理值。

还有一种更好的方法可以使用prepare()

$stm = $pdo->prepare('SELECT P.URL, P.Title, P.Subtitle, P.MetaTitle, P.MetaDesc, P.KW, P.Live, PB.Common, PB.First, PB.Middle, PB.Last, PB.Prefix, PB.Suffix, PB.Born, PB.Died, PB.Birth_Place, PB.Death_Place, PB.Nationality, Brf.Site, Brf.Brief, PC.Class, PX.Article PXA, PX.Pagedex PXP, IVR.Article IVRA, IVR.Pagedex IVRP, SM.Article SMA, SM.Pagedex SMP
FROM people P
LEFT JOIN people_1_bio PB ON PB.URL = P.URL
LEFT JOIN people_1_class PC ON PC.URL = P.URL
LEFT JOIN people_briefs Brf ON Brf.URL = P.URL
LEFT JOIN people_articles_px PX ON PX.URL = P.URL
LEFT JOIN people_articles_ivr IVR ON IVR.URL = P.URL
LEFT JOIN people_articles_sm SM ON SM.URL = P.URL
WHERE P.URL LIKE :url AND P.Site = :site
GROUP BY Class',
array( ) );

$stm->execute( array( ':url'=> $MyURL, ':site' => $MySiteID ) );

while( $row = $stm->fetch(PDO::FETCH_ASSOC ) {

    // your loop here

PDO演示建议？

1 个答案: