如何使用 PHP 的 PDO 检查数据库查询返回的结果

How do I check if my result set is empty using PDO in PHP?

$SQL = "SELECT ......... ORDER BY lightboxName ASC;";
$STH = $DBH->prepare($SQL);
$STH->bindParam(':member_id', $member_id);
$STH->execute();
$STH->setFetchMode(PDO::FETCH_ASSOC);

while($row = $STH->fetch()) {
    $lightbox_name = $row['lightboxName'];
    $lightbox_id = $row['lightboxID'];
    echo '<option value="'.$lightbox_id.'">'.$lightbox_name.'</option>';
}

我以前是这样做的:

$result = mysql_query("SELECT ...... ORDER BY lightboxName ASC;");
if(!$result) { echo 'No results found!'; }

但是刚刚开始使用 PDO 和准备好的语句并且检查 $STH 似乎没有按预期工作 - 它总是有价值的！

$rows_found = $STH->rowCount();