loops - 将 SQL 查询/循环转换为 PDO

Question

我正在尝试通过循环将 PDO 结果显示在表格中。但是目前它只是显示一个白页。对缺少的内容有什么建议吗？或者为什么页面是空白的？

<?php

try {  $conn = new PDO("pgsql:host=localhost port=5432 dbname=riverflies_gis", "opengeo", "opengeo");
 echo "PDO connection object created";
 echo "<br>";
}
catch(PDOException $e) {
  echo $e->getMessage();
}

  $sql  = "SELECT admin_name, adminuser_id, group_id FROM adminuser_tbl";
  $stmt = $conn->prepare($sql);
  $stmt->execute();
  $data = $stmt->fetchAll();
?>

        <table border='1' cellpadding='10'>
        <tr>
        <th>ID</th>
        <th>adminuser</th>
        <th>group_id</th>
        <th></th>
       </tr>

<?php foreach ($data as $row): ?>
<tr>
<td><?=$row['adminuser_id']?></td>
<td><?=$row['admin_name']?></td>
<td><?=$row['group_id']?></td>
</tr>
<?php endforeach ?>
</table>

Answer 1

请永远不要将数据库操作与HTML输出混合。

PDO 尤其适合它。首先获取您的数据：

$sql  = "SELECT admin_name, adminuser_id, group_id FROM adminuser_tbl";
$stmt = $conn->prepare($sql);
$stmt->execute();
$data = $stmt->fetchAll();

然后在模板中输出：

<table border='1' cellpadding='10'>
 <tr>
  <th>ID</th>
  <th>First Name</th>
  <th>Last Name</th>
  <th></th>
  <th></th>
 </tr>
<? foreach ($data as $row): ?>
 <tr>
  <td><?=$row['id']?></td>
  <td><?=$row['firstname']?></td>
  and so on
 </tr>
<? endforeach ?>
</table>

看看你的输出代码有多漂亮和干净