比较两个不同的mysqli_fetch_array与PHP的结果-英雄云拓展知识分享

我创建了一个数据库，其中保存有关利用程序的信息。这些利用程序可以链接到 垂直的。我设计了DB，以致于我有一个表格，以获得有关每一个利用程序的标准信息，其中包括一个自动插入ID的名称等。我有另外一个桌子列出了所有不同的行业/垂直行业。

除这2个表外，我还有第3个连接两张表，看起来像这样（我在PHP数组中显示了它，由于我认为它更容易浏览）：

  $verticals_joint = array(
array('vertical_joint_id' => '1','vertical_id' => '11','demo_id' => '173'),
array('vertical_joint_id' => '2','vertical_id' => '12','demo_id' => '173'),
array('vertical_joint_id' => '3','vertical_id' => '13','demo_id' => '173'),
array('vertical_joint_id' => '4','vertical_id' => '2','demo_id' => '174'),
array('vertical_joint_id' => '5','vertical_id' => '4','demo_id' => '174'),
array('vertical_joint_id' => '6','vertical_id' => '3','demo_id' => '175'),
array('vertical_joint_id' => '7','vertical_id' => '4','demo_id' => '175'),
array('vertical_joint_id' => '8','vertical_id' => '8','demo_id' => '176'),
array('vertical_joint_id' => '9','vertical_id' => '9','demo_id' => '176'),
array('vertical_joint_id' => '10','vertical_id' => '1','demo_id' => '92'),
array('vertical_joint_id' => '11','vertical_id' => '3','demo_id' => '92'),
array('vertical_joint_id' => '12','vertical_id' => '12','demo_id' => '92'),
array('vertical_joint_id' => '13','vertical_id' => '1','demo_id' => '179'),
array('vertical_joint_id' => '14','vertical_id' => '3','demo_id' => '179'),
array('vertical_joint_id' => '15','vertical_id' => '4','demo_id' => '179'),
array('vertical_joint_id' => '16','vertical_id' => '2','demo_id' => '180'),
array('vertical_joint_id' => '17','vertical_id' => '4','demo_id' => '180')
);

Vertical_ID将行业/垂直与利用程序/演示联系起来。 emo_id援用利用程序（或我称之为演示）。

现在是我的问题。我在PHP中提出了一段时间的循环，然后在其中嵌套了一个If statement，因此我可以显示所有垂直行业，并标记为给定利用程序创建的垂直行业。例如。这就是我想要实现的：

<select id="Vertical[]" class="form-control verticalText" multiple="multiple">
<option value="1">Education</option>
<option value="2">Manufacturing</option>
<option value="3">State, Local or Provincial Government</option>
<option value="4">Federal Government</option>
<option value="5">Other</option>
<option value="6">Transportation and Logistics</option>
<option value="7">Healthcare</option>
<option value="8">Petrochemical</option>
<option value="9">Utilities</option>
<option value="10">Public Safety</option>
<option value="11" selected>Hospitality</option>
<option value="12" selected>Wholesale Distribution</option>
<option value="13" selected>Human Services</option>
<option value="14">Retail</option>

这就是我要实现的目标，但是当我使用时循环时，它只会正确选择 热忱好客 并且不选择 批发区 或 人工服务.

我的whier-loop +嵌套如果陈说看起来像这样：

//Gathers the names of all existing verticals.
$vertical_query  = "SELECT * FROM demos.verticals";
$result_vertical = mysqli_query($con, $vertical_query);
//Gathers information about the particular application you are comparing with.
//It retrieves the verticals for a particular app/demo id.
//For this example I used id 173
$joint_query  = "SELECT o.vertical_id, o.vertical_name FROM demos.alldemos alld
LEFT JOIN demos.verticals_joint j ON alld.id = j.demo_id
LEFT JOIN demos.verticals o ON o.vertical_id = j.vertical_id
WHERE alld.id = 173";
$result_joint = mysqli_query($con, $joint_query);
$compare      = mysqli_fetch_array($result_joint);
$output       = '';
// while there are Verticals to be listed.
while ($row_vertical = mysqli_fetch_array($result_vertical)) {
// If a vertical is already selected for this particular app id,
if ($compare['vertical_name'] == $row_vertical["vertical_name"]) {
//then add the word select to the option so it will be selected
$output .= '<option value="'.$row_vertical["vertical_id"].'" selected>'.$row_vertical['vertical_name'].'</option>';
} elseif ($compare['vertical_name'] != $row_vertical["vertical_name"]) {
//Otherwise just print out the normal option without 'selected'.
$output .= '<option value="'.$row_vertical["vertical_id"].'">'.$row_vertical["vertical_name"].'</option>';
}
}
echo $output;

您是不是知道为何它仅比较我的SQL中的第一项与我的其他选择查询中的垂直行业进行比较？您会建议做不同的事情吗？