PHP MYSQL - 根据行号是否匹配行号填充 HTML 表编号行

所以，基本上我正在尝试制作数据中心驾驶室图。我们有一个 Excel 电子表格，但它不容易更新，也不容易搜索。我的 MySQL 数据库中有三个表；数据库是：机架，表格是：机柜、设备和数据中心 - 每个表格中的每一行代表它是什么。机柜表有一列指定其 U 高度（某些数据中心的某些机柜比其他机柜高）。所以，当php绘制一个柜子时，它会按照相应的高度绘制柜子。到目前为止，关于数据中心及其包含的机柜及其各自高度的分组一切正常。我的问题是，每个机柜似乎无法安装多于一台设备。这是整个页面，MySQL 数据库设置如下：

<SCRIPT LANGUAGE="JavaScript" type="text/javascript">
<!--
    function clickHandler(e)
    {
        var targetId, srcElement, targetElement;
        if (window.event) e = window.event; 
        srcElement = e.srcElement? e.srcElement: e.target;
        if (srcElement.className == "Outline")
        {
                targetId = srcElement.id + "d";
                targetElement = document.getElementById(targetId);

            if (targetElement.style.display == "none")
                {
                        targetElement.style.display = "";
                        srcElement.src = "images/minus.gif";
                    } 
            else
                {
                    targetElement.style.display = "none";
                    srcElement.src = "images/plus.gif";
                }
        }
    }
    document.onclick = clickHandler;
-->
</SCRIPT>
<noscript>You need Javascript enabled for this page to work correctly</noscript>
<?
function sql_conn()
{
    $username="root";
    $password="root";
    $database="racks";
    $server="localhost";

    @mysql_connect($server,$username,$password) or die("<h2 align=\"center\" class=\"red\">[<img src=\"images/critical.gif\" border=\"0\">] Unable to connect to $server [<img src=\"images/critical.gif\" border=\"0\">]</h2>");
    @mysql_select_db($database) or die("<h2 align=\"center\" class=\"red\">[<img src=\"images/critical.gif\" border=\"0\">] Unable to select $database as a database [<img src=\"images/critical.gif\" border=\"0\">]</h2>");
}

sql_conn();
$sql_datacenters="SELECT * FROM `datacenters`";

$sql_devices="SELECT * FROM `devices`";
$result_datacenters=mysql_query($sql_datacenters);
$result_devices=mysql_query($sql_devices);
$j=0;
echo "<table border='1' style='float:left;'>";
while ($datacenters_sqlrow=mysql_fetch_array($result_datacenters))
{
    echo "<tr><td>";
    echo "<h2 class='black' align='left'>";
    echo "<IMG SRC='images/plus.gif' ID='Out" . $j . "' CLASS='Outline' STYLE='cursor:hand;cursor:pointer'>"; // fancy icon for expanding-collapsing section
    echo " " . $datacenters_sqlrow['rack'] . ": " . $datacenters_sqlrow['cagenum'] . "</h2>"; // datacenter name and cage number
    echo "<div id=\"Out" . $j . "d\" style=\"display:none\">"; // opening of div box for section that is to be expanded-collapsed
    echo "<h3>" . $datacenters_sqlrow['notes'] . "</h3>"; // datacenter notes
    $sql_cabinets="SELECT * FROM `cabinets` WHERE `datacenter` = '$datacenters_sqlrow[0]' ORDER BY `cabinetnumber` ASC";
    $result_cabinets=mysql_query($sql_cabinets);
    while ($cabinets_sqlrow=mysql_fetch_array($result_cabinets))
    {
        $sql_devices="SELECT * FROM `devices` WHERE `datacenter` = '$datacenters_sqlrow[0]' AND `cabinet` = '$cabinets_sqlrow[1]' ORDER BY `ustartlocation` ASC";
        $result_devices=mysql_query($sql_devices);
        $num_devices=mysql_numrows($result_devices);
        echo "<table border='1' style='float:left;'>"; // opening of table for all cabinets in datacenter
        echo "<tr><td colspan='2' align='middle'>" . $cabinets_sqlrow[1] . "</td></tr>"; // cabinet number, spans U column and device name column
        while($row = mysql_fetch_array($result_devices))
        {
            $server = $row['devicename'];
            $ustart = $row['ustartlocation'];
        }
        for ($i = 0; $i < $cabinets_sqlrow[2]; $i++) // iterates through number of U in cabinet     
        {   
            $u = $cabinets_sqlrow[2] - $i; // subtracts current $i value from number of U in cabinet since cabinets start their numbers from the bottom up
            echo "<tr>";
            echo "<td width='15px' align='right'>$u</td>"; // U number
            echo "<td width='150px' align='middle'>";
            if ($u == $ustart) // determines if there is a device starting at this U
            {echo $server;} // device name
            else
            {echo "empty";} // empty space in cabinet
            echo "</td>";
            echo "</tr>";
        }
        $server="";
        $ustart="";

        echo "</table>"; // closes table opened in row 65
    }
    echo "</td></tr>";
    echo "</div>"; // close for div box that needs expanding-collapsing by fancy java
    $j++; // iteration for the fancy java expand-collapse
}
echo "</table>";
mysql_close();
?>

这是 MySQL 设置：

-- phpMyAdmin SQL Dump
-- version 3.5.1
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Nov 02, 2012 at 02:13 AM
-- Server version: 5.5.25
-- PHP Version: 5.4.4

SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";

--
-- Database: `racks`
--

-- --------------------------------------------------------

--
-- Table structure for table `cabinets`
--

CREATE TABLE `cabinets` (
  `id` tinyint(3) NOT NULL AUTO_INCREMENT,
  `cabinetnumber` varchar(25) NOT NULL,
  `numberofu` varchar(3) NOT NULL,
  `datacenter` tinyint(3) NOT NULL,
  KEY `id` (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=6 ;

--
-- Dumping data for table `cabinets`
--

INSERT INTO `cabinets` (`id`, `cabinetnumber`, `numberofu`, `datacenter`) VALUES
(1, '0101', '45', 2),
(2, '0102', '45', 2),
(3, '0101', '50', 1),
(4, '0102', '50', 1),
(5, '0103', '50', 1);

-- --------------------------------------------------------

--
-- Table structure for table `datacenters`
--

CREATE TABLE `datacenters` (
  `id` tinyint(3) NOT NULL AUTO_INCREMENT,
  `rack` varchar(20) NOT NULL,
  `cagenum` varchar(255) NOT NULL,
  `notes` longtext NOT NULL,
  KEY `id` (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ;

--
-- Dumping data for table `datacenters`
--

INSERT INTO `datacenters` (`id`, `rack`, `cagenum`, `notes`) VALUES
(1, 'CAGE1', '', ''),
(2, 'CAGE2', '', ''),
(3, 'CAGE3', '', ''),
(4, 'CAGE4', '', ''),
(5, 'CAGE5', '', ''),
(6, 'CAGE6', '', ''),
(7, 'CAGE7', '', '');

-- --------------------------------------------------------

--
-- Table structure for table `devices`
--

CREATE TABLE `devices` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `devicename` varchar(255) NOT NULL,
  `datacenter` varchar(255) NOT NULL,
  `cabinet` varchar(255) NOT NULL,
  `frontorrear` tinyint(3) NOT NULL,
  `ustartlocation` varchar(255) NOT NULL,
  `usize` varchar(255) NOT NULL,
  `spare1` varchar(255) NOT NULL,
  `spare2` varchar(255) NOT NULL,
  `spare3` varchar(255) NOT NULL,
  KEY `id` (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=4 ;

--
-- Dumping data for table `devices`
--

INSERT INTO `devices` (`id`, `devicename`, `datacenter`, `cabinet`, `frontorrear`, `ustartlocation`, `usize`, `spare1`, `spare2`, `spare3`) VALUES
(1, 'SERVER1', '1', '0101', 1, '33', '1', '', '', ''),
(2, 'SERVER2', '1', '0102', 1, '36', '1', '', '', ''),
(3, 'SERVER3', '1', '0101', 1, '40', '2', '', '', '');

为了直接解决这个问题（我稍后会详细介绍），您将迭代完整的设备列表并then- 循环完所有这些之后 - 您尝试显示它们。因此，您仅显示最终触摸的设备。

您当前的代码（被截断）是：

while($row = mysql_fetch_array($result_devices)) {
    $server = $row['devicename'];
    $ustart = $row['ustartlocation'];
}
for ($i = 0; $i < $cabinets_sqlrow[2]; $i++) {
    $u = $cabinets_sqlrow[2] - $i;
    ...
    if ($u == $ustart) {
        echo $server;
    }
    ...
}

如果我理解您要做什么，您需要将每个设备存储到“devices”数组中，并在每次迭代期间循环遍历它for环形。尝试类似的方法：

$devices = array();
while($row = mysql_fetch_array($result_devices)) {
    $devices[] = array(
        'server' => $row['devicename'],
        'ustart' => $row['ustartlocation']
    );
}
for ($i = 0; $i < $cabinets_sqlrow[2]; $i++) {
    ...
    $output = 'empty';
    foreach ($devices as $device) {
        if ($u == $device['ustart']) {
            $output = $device['server'];
            break;
        }
    }
    echo $output;
    ...
}

可以使用更优雅的方式来完成相同的任务ustartlocation作为数组的索引，但它需要ustartlocation对于单个设备/服务器来说是唯一的：

$devices = array();
while($row = mysql_fetch_array($result_devices)) {
    $devices[$row['ustartlocation']] = $row['devicename'];
}
for ($i = 0; $i < $cabinets_sqlrow[2]; $i++) {
    ...
    echo (isset($devices[$u]) ? $devices[$u] : 'empty');
    ...
}

此方法将不再需要每次循环遍历设备列表，但同样 - 它要求ustartlocation是独特的。

旁注（额外的、非特定答案的批评）

1. 在代码的开头执行$sql_devices="SELECT * FROMdevices"; and $result_devices=mysql_query($sql_devices);，但永远不要使用这个对象。它可以而且应该被删除，因为它是一个额外的（相当重的）查询。

2. 在第二while-loop 你有这条线$num_devices=mysql_numrows($result_devices);。没有 PHP 函数mysql_numrows()，我相信这是一个拼写错误mysql_num_rows() http://php.net/mysql_num_rows函数（或者你有一个自定义编写的函数来完成同样的事情。此外，$num_devices变量从未使用过，因此实际上可以完全删除该行。

3. 你正在使用旧的和即将被弃用的mysql_函数（查看这些函数的任何文档页面顶部的警告消息；这里是mysql_connect() http://php.net/manual/en/function.mysql-connect.php以供参考）。我以及社区建议您升级到mysqli_ http://php.net/manual/en/book.mysqli.php or PDO http://php.net/manual/en/book.pdo.php方法。

4. 您的代码容易出现未经清理的 SQL 错误，不仅限于 SQL 注入，因为您似乎没有直接从用户输入中获取输入，但也不排除此因素。例如，如果cabinet or datacenter值包含单引号？既然你正在使用mysql_方法，我建议你用以下方法包装每个方法mysql_real_escape_string() http://php.net/mysql_real_escape_string在数据库调用中使用它们之前：$sql_cabinets="SELECT * FROM cabinets WHERE datacenter = '" . mysql_real_escape_string($datacenters_sqlrow[0]) . "' ORDER BY cabinetnumber";