php - 按列对表格中的数据进行排序

Question

我想在 html 表的标题中点击时对 mysql 数据库中的数据进行排序。我写了这段代码:

$username = $_SESSION['username']; // gets the username

echo "<table class='normal_table'>";

$new_word = mysql_query("SELECT * FROM new_word WHERE username='$username'");
$new_word2 = mysql_query($new_word);

echo " 

<tr>
<th><a href='test.php?sort=cz'>Czech:</a></th>
<th><a href='test.php?sort=en'>English:</a></th>
<tr>";

if ($_GET['sort'] == 'cz')
{
 $new_word .= " ORDER BY cz";
}
elseif ($_GET['sort'] == 'en')
{
 $new_word .= " ORDER BY en";
}

while($new_word2 = mysql_fetch_array($new_word)){

echo "
<tr>
<td> ".$new_word2['cz']."</td>
<td>".$new_word2['en']."</td>
</tr>

"; }

echo "</table>";

但是屏幕上没有显示任何数据:( 我做错了什么？

Answer 1

您正在执行您的查询

$new_word = mysql_query("SELECT * FROM new_word WHERE username='$username'");

然后尝试附加到该查询对象

$new_word .= " ORDER BY en";

您需要先构建查询字符串

所以

$sql =  "SELECT * FROM new_word WHERE username='$username'"

附加你的ORDER BY

$sql .= " ORDER BY en";

然后执行

$new_word = mysql_query($sql);

编辑:同时删除 $new_word2 = mysql_query($new_word); 并更改您的 while 以使用 $new_world 正如 Uttam Kadam 在他们的 answer 中所说