为什么运行后只能输出一行结果，我是想输出满足age=20的全部结果的。 代码哪里写错了？

Question

数据库中有一个表test为：id name age 
$sql="select * from test where age=20";
$result=mysql_query($sql);
echo "<table border='1' cellspacing=0px>
<tr>
<th>id</th>
<th>name</th>
<th>age</th>
</tr>";
while ($row=mysql_fetch_array($result)) {
echo "<tr>";
echo "<td>".$row['id']."</td>";
echo "<td>".$row['name']."</td>";
echo "<td>".$row['age']."</td>";
echo "</tr>";
}
echo "</table>";

Answer 1

你使用的函数就是单条的。请换成mysql_fetch_field<?php$con&nbsp;=&nbsp;mysql_connect("localhost",&nbsp;"hello",&nbsp;"321");if&nbsp;(!$con)&nbsp;&nbsp;{&nbsp;&nbsp;die('Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;.&nbsp;mysql_error());&nbsp;&nbsp;}&nbsp;$db_selected&nbsp;=&nbsp;mysql_select_db("test_db",$con);&nbsp;$sql&nbsp;=&nbsp;"SELECT&nbsp;*&nbsp;from&nbsp;Person";$result&nbsp;=&nbsp;mysql_query($sql,$con);&nbsp;while&nbsp;($property&nbsp;=&nbsp;mysql_fetch_field($result))&nbsp;&nbsp;{&nbsp;&nbsp;echo&nbsp;"Field&nbsp;name:&nbsp;"&nbsp;.&nbsp;$property->name&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Table&nbsp;name:&nbsp;"&nbsp;.&nbsp;$property->table&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Default&nbsp;value:&nbsp;"&nbsp;.&nbsp;$property->def&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Max&nbsp;length:&nbsp;"&nbsp;.&nbsp;$property->max_length&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Not&nbsp;NULL:&nbsp;"&nbsp;.&nbsp;$property->not_null&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;&nbsp;echo&nbsp;"Primary&nbsp;Key:&nbsp;"&nbsp;.&nbsp;$property->primary_key&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Unique&nbsp;Key:&nbsp;"&nbsp;.&nbsp;$property->unique_key&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;&nbsp;echo&nbsp;"Mutliple&nbsp;Key:&nbsp;"&nbsp;.&nbsp;$property->multiple_key&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Numeric&nbsp;Field:&nbsp;"&nbsp;.&nbsp;$property->numeric&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"BLOB:&nbsp;"&nbsp;.&nbsp;$property->blob&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Field&nbsp;Type:&nbsp;"&nbsp;.&nbsp;$property->type&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Unsigned:&nbsp;"&nbsp;.&nbsp;$property->unsigned&nbsp;.&nbsp;"<br&nbsp;/>";&nbsp;&nbsp;echo&nbsp;"Zero-filled:&nbsp;"&nbsp;.&nbsp;$property->zerofill&nbsp;.&nbsp;"<br&nbsp;/><br&nbsp;/>";&nbsp;&nbsp;&nbsp;}&nbsp;mysql_close($con);?>