查询删除所有条目而不是选定的条目答案

【问题标题】：Query erases all entries instead of the ones selected查询删除所有条目而不是选定的条目
【发布时间】：2019-02-20 12:05:08
【问题描述】：

我制作了一个从 joomla 数据库填充的下拉菜单。该菜单包含来自特定用户的峰名称。这部分工作顺利。当用户从下拉菜单中选择峰名并单击删除按钮时，查询应该只删除具有特定用户的id（$link_id）和所选顶部的名称（$vrh_name2）的行。

在我的例子中，查询会删除该用户的所有行，而不管所选顶部的名称如何

我在哪里做错了？

<!DOCTYPE html>
<html>
<body>

<?php
echo '<div class="sender">';
$link_id = JRequest::getInt('link_id'); 
echo '<h4>Form for delete peak</h4>';

// Creating Dropdown menu from database
   
$db = JFactory::getDbo();
$query2 = $db->getQuery(true);
$query2->select('peak_name');
$query2->from($db->qn('#__climbing'));
$query2->where($db->quoteName('#__climbing.link_id')." = ".$db->quote($link_id));
$query2->order('peak_id ASC');
$db->setQuery($query2);
$peaks_list2 = $db->loadColumn();
$peaks_select2  = '<select name2="name2" id2="peaks">';
$peaks_select2 .= '<option value="">-- Select peak for delete --</option>';

foreach($peaks_list2 as $p2){
    $peaks_select2 .= '<option value="' . $p2 . '">' . $p2 . '</option>';  
}
$peaks_select2 .= '</select>';
?>

<form name="lista2" method="post" action="">
<?php echo $peaks_select2; ?>
<input type="submit" name="submit2" value="Delete" />
</form>
<?php

if(isset($_POST['submit2']))
{
$vrh_name2 = $_POST['name2'];

// Delete peak query

$db = JFactory::getDbo();
$q_4 = $db->getQuery(true);
$q_4->delete($db->quoteName('#__climbing'));
$q_4->where($db->quoteName('#__climbing.link_id')." = ".$db->quote($link_id))." AND ".($db->quoteName('#__climbing.peak_name')." = ".$db->quote($vrh_name2));
$db->setQuery($q_4);
$db->execute();
}
echo '</div>';
?>
</body> 
</html>

【问题讨论】：

标签： mysql joomla

【解决方案1】：

别忘了some of the past advice that I have offered。

在这个问题中最引人注目的是，$peaks_select2 = '<select name2= 不起作用。 name 属性必须是纯正的。

通过先执行潜在的删除操作，您可以让您的用户在删除后进行删除，并始终在选择中看到最新的数据。

我不喜欢你使用peak_name 作为你的标识符。您的表有一个peak_id，在大多数情况下，这些预计会自动递增并且是唯一的，并且它们是专业人士关联相关数据的方式。（您应该改变您的设计以采用这种做法。）

When an option's value attribute value is the same as the option's text value, there is no need to declare the name attribute.因为我建议使用 id，所以我声明了 name 属性。

未经测试的sn-p：

<!DOCTYPE html>
<html>
<body>

<?php
// get the $_POST['submit'] value; if missing, set as empty string (WORD is a Joomla-specific filter that strips unwanted characters for security reasons)
$action = JFactory::getApplication()->input->post->get('submit', '', 'WORD')

// get the $_POST['peak_id'] value; if missing set as 0 (INT strips any character that is not a digit)
$peak_id = JFactory::getApplication()->input->post->get('peak_id', 0, 'INT');

// try to get the $_POST['link_id'] value; if it is missing, try from $_GET['link_id']
$hiker_id = JFactory::getApplication()->input->post->get('link_id', 0, 'INT');
if (!$hiker_id)
{
    // there was no submission (this is the first load of the page)
    $hiker_id = JFactory::getApplication()->input->get->get('link_id', 0, 'INT');
}
echo "<div>Link Id: $hiker_id</div>";

$db = JFactory::getDbo();

if ($action === 'Delete' && $peak)  // if action is Delete and $peak is not empty or 0
{
    $delete_query = $db->getQuery(true)
        ->delete("#__climbing")
        ->where([
            "link_id = " . (int) $hiker_id,
            "peak_id = " . (int) $peak_id
        ]);
    $db->setQuery($delete_query);
    $db->execute();
    if ($db->getAffectedRows())  // check for successful deletion (if at least one row was deleted)
    {
        echo "<div>Successfully deleted row for hiker#: $hiker_id, peak#: $peak_id</div>";
    }
    else
    {
        echo "<div>Failed to delete row for hiker#: $hiker_id, peak#: $peak_id</div>";
    }
}

// now query the table for the fresh data after the (potential) delete was performed
$peaks_query = $db->getQuery(true)
    ->select("peak_id, peak_name")
    ->from("#__climbing")
    ->where("link_id = " . (int) $link_id)
    ->order("peak_id");
$db->setQuery($peaks_query);

$peaks_select = '<select name="peak_id">';
$peaks_select .= '<option value="0">-- Select peak to delete --</option>';
if (!$results = $db->loadAssocList())  // there were no rows in the result set
{
    // no peaks found for $link_id
}
else
{
    foreach ($results as $row)
    {
        $peaks_select .= "<option value=\"{$row['peak_id']}\">{$row['peak_name']}</option>";  // create option with name as text and id as the value
    }
}
$peaks_select .= '</select>';

// print the simple form...
?>
<div class="sender">
    <h4>Peak Delete Form</h4>
    <form method="post" action="">
        <?=$peaks_select?>
        <input type="hidden" name="link_id" value="<?=$hiker_id?>">
        <input type="submit" name="submit" value="Delete" />
    </form>
</div>
</body> 
</html>

【讨论】：

谢谢，我试试这个
我的 php 知识很低，我不知道一切是如何工作的。我尝试了这段代码但没有工作，我找不到原因。但是您关于 select name2= 的建议对我有所帮助。有一个错误。非常感谢
作为发帖人，我有责任解释我的回答中任何令人困惑的地方。欢迎您提出任何澄清。
我不明白这是怎么工作的： $peak_id = JFactory::getApplication()->input->get->get('peak_id', 0, 'INT');因为我有错误未知变量 $peak_id
@Midhat 我刚刚做了几处更正。请单击我的编辑历史记录（在我的图片左侧）以查看突出显示的更改。

【解决方案2】：

您好，如果我理解您的尝试并根据以下信息：

https://docs.joomla.org/Inserting,_Updating_and_Removing_data_using_JDatabase

您可以使用此代码执行删除：

<!DOCTYPE html>
<html>
<body>

<?php
echo '<div class="sender">';
$link_id = JRequest::getInt('link_id'); 
echo '<h4>Form for delete peak</h4>';

// Creating Dropdown menu from database
.
$db = JFactory::getDbo();
$query2 = $db->getQuery(true);
$query2->select('peak_name');
$query2->from($db->qn('#__climbing'));
$query2->where($db->quoteName('#__climbing.link_id')." = ".$db->quote($link_id));
$query2->order('peak_id ASC');
$db->setQuery($query2);
$peaks_list2 = $db->loadColumn();
$peaks_select2  = '<select name2="name2" id2="peaks">';
$peaks_select2 .= '<option value="">-- Select peak for delete --</option>';

foreach($peaks_list2 as $p2){
    $peaks_select2 .= '<option value="' . $p2 . '">' . $p2 . '</option>';  
}
$peaks_select2 .= '</select>';
?>

<form name="lista2" method="post" action="">
<?php echo $peaks_select2; ?>
<input type="submit" name="submit2" value="Delete" />
</form>
<?php

  if(isset($_POST['submit2']))
  {
     $vrh_name2 = $_POST['name2'];

     // Delete peak query
     $db = JFactory::getDbo();
     $q_4 = $db->getQuery(true);
     // delete all row where this conditions link_id and peak_name
    $conditions = array(
        $db->quoteName('link_id') . ' =' . $db->quote($link_id)), 
        $db->quoteName('peak_name') . ' = ' . $db->quote($vrh_name2))
    );
    $q_4->delete($db->quoteName('#__climbing'));
    $q_4->where($conditions);
    $db->setQuery($q_4);

    $db->execute();
}
echo '</div>';
?>
</body> 
</html>

【讨论】：

谢谢，但这也行不通。删除表格中的所有内容
@Midhat，对不起，我没有测试平台。我有测试的更新代码
谢谢@pascal sanchez 现在不会删除任何东西
可能是因为我的英语不好导致的误会，但目前还不行。现在，当我选择要删除的项目并单击删除时，不会删除任何内容