为什么我的PHP没有显示任何东西? (代码包括在内)
This code should give a table of the table cats. However, it shows a blank page. It seems the query part does not work. It cannot go to 'var_dump($results)
'. However, I can create a table using codes having been commented. So what is the problem ?
<?php
require_once "login.php";
$db_server = mysql_connect($db_hostname, $db_username, $db_password);
if(!$db_server)
die("Unable to connect: ".mysql_error());
mysql_select_db($db_database, $db_server) or die("Unable to select a db: ".mysql_error());
/*
$query = "CREATE TABLE cats
(
id SMALLINT NOT NULL AUTO_INCREMENT,
family VARCHAR(32) NOT NULL,
name VARCHAR(32) NOT NULL,
age TINYINT NOT NULL,
PRIMARY KEY (id)
)";
mysql_query($query) or die("Create cats DB failed: ".mysql_error());
*/
$query = "DESCRIBE cats";
$results = mysql_query($query)
var_dump($results);
if(!$results)
die("Error-line22: ".mysql_error());
else
echo $results."<br />";
$rows = mysql_num_rows($results);
echo "<table>";
echo "
<tr> <th>Column</th> <th>Type</th> <th>NULL</th> <th>Key</th> </tr>";
for ($j = 0; $j < $rows; ++$j)
{
$row = mysql_fetch_row($results);
echo "<tr>";
for ($k = 0; $k < 4; ++$k)
echo "<td>$row[$k]</td>";
echo "</tr>";
}
echo "</table>";
mysql_close($db_server);
?>
此代码应该提供表格的表格。 但是,它显示一个空白页面。 似乎查询部分不起作用。 它不能转到' var_dump($ results) code>'。 但是,我可以使用已注释的代码创建表。 那么问题是什么? p>
&lt;?php
require_once“login.php”;
$ db_server = mysql_connect($ db_hostname,$ db_username,$ db_password);
if(!$ db_server)
die(“无法连接:”。mysql_error());
mysql_select_db($ db_database,$ db_server)或die(“无法选择数据库:”。mysql_error());
/ *
$ query =“CREATE TABLE cats
(
id SMALLINT NOT NULL AUTO_INCREMENT,
family VARCHAR(32)NOT NULL,
name VARCHAR(32)NOT NULL,
age TINYINT NOT NULL,
PRIMARY KEY(id)
)“;
mysql_query($ query)或die(”Create cats DB failed:“。mysql_error());
* /
$ query =”DESCRIBE cats“;
$ results = mysql_query($ query)
var_dump($ results);
if(!$ results)
die(“Error-line22:”。mysql_error());
else
echo $ results。“&lt; br /&gt;“;
$ rows = mysql_num_rows($ results);
echo”&lt; table&gt;“;
echo”
&lt; tr&gt;&lt; th&gt; Column&lt; / th&gt;&lt; th&gt; ;键入&lt; / th&gt;&lt; th&gt; NULL&lt; / th&gt;&lt; th&gt;键&lt; / th&gt;&lt; / tr&gt;“;
for($ j = 0; $ j&lt; $ rows; ++ $ j)
{
$ row = mysql_ fetch_row($ results);
echo“&lt; tr&gt;”;
for($ k = 0; $ k&lt; 4; ++ $ k)
echo“&lt; td&gt; $ row [$ k]&lt; / td&gt;”;
echo“&lt; / tr&gt;”;
}
echo“&lt; / table&gt; “;
mysql_close($ db_server);
?&gt;
code> pre>
div>
The mysql_query() line is missing a ';' at the end:
$query = "DESCRIBE cats";
$results = mysql_query($query);
var_dump($results);