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[英]mysql selecting two DISTINCT value from two different columns from a table
[英]SELECTING DISTINCT values from two different COLUMNS of the same table
我有一个SQL表看起来像这样。
id name cname
1 Ash abc
2 Ash abc
3 Ashu abc
4 Ashu xyz
5 Yash xyzz
6 Ash xyyy
我希望用户从显示DISTINCT名称值及其正常工作的第一个选择下拉列表中选择一个值。
第一选择:
<select id="select1" required="required" class="custom-select standard">
<option value="0" selected="selected">Choose Category</option>
<?php
$resultd = mysqli_query($mysqli,"SELECT DISTINCT name FROM advertise");
if ($resultd)
{
while($tier = mysqli_fetch_array($resultd))
{
echo '<option value="' .$tier['name'] . '">' . $tier['name'] . '</option>';
}
}
?>
</select>
现在我想显示基于第一个的第二个选择下拉框的值。 我为此使用的jQuery是:
<script>
$(function(){
var conditionalSelect = $("#select2"),
// Save possible options
options = conditionalSelect.children(".conditional").clone();
$("#select1").change(function(){
var value = $(this).val();
conditionalSelect.children(".conditional").remove();
options.clone().filter("."+value).appendTo(conditionalSelect);
}).trigger("change");
});
</script>
第二选择框
<select id="select2" required="required" class="custom-select standard">
<option value="0" selected="selected">Choose Location</option>
<option class="conditional name" value="">cname</option>
</select>
我只想知道什么是PHP查询,我需要使用它来在基于第一个的第二选择框中获取值。 我做了很多尝试来找到解决方案,但是我没有找到任何可以从数据库中获取其值的解决方案...在此先感谢...
如果您做的事情有所不同,则可能不需要第二查询和所有这些复杂性。 这意味着,您可以使用一个查询来实现您的目标。 下面的代码演示了如何。 注意:此解决方案使用JQuery使事情变得更简单。
为了测试 只需将Code IS IS IS 复制并粘贴 到新文件中,然后查看其是否按预期工作。
干杯和好运!
<?php
// USE YOUR CONNECTION DATA... PDO WOULD BE HIGHLY RECOMMENDED.
// INTENTIONALLY USING mysqli (NOT RECOMMENDED) TO MATCH YOUR ORIGINAL POST.
$conn = mysqli_connect("localhost", "root", 'root', "test");
if (mysqli_connect_errno()){
die("Failed to connect to MySQL: " . mysqli_connect_error());
}
$resourceID = mysqli_query($conn, "SELECT * FROM advertise");
$all = mysqli_fetch_all($resourceID, MYSQLI_ASSOC);
$uniques = [];
$options1 = "";
if( !empty($all) ){
foreach($all as $intKey=>$advertiseData) {
$key = $advertiseData['name'];
$cName = getCNameForName($all, $key);
if (!array_key_exists($key, $uniques)) {
$uniques[$key] = $advertiseData;
$options1 .= "<option value='{$key}' data-cname='{$cName}'>";
$options1 .= $key . "</option>";
}
}
}
function getCNameForName($all, $name){
$result = [];
foreach($all as $iKey=>$data){
if($data["name"] == $name){
$result[] = $data['cname'];
}
}
return $result ? implode(", ", array_unique($result)) : "";
}
?>
<html>
<body>
<div>
<select id="select1" required="required" class="custom-select standard">
<option value="0" selected="selected">Choose Category</option>
<?php echo $options1; ?>
</select>
<select id="select2" required="required" class="custom-select standard">
<option value="0" selected="selected">Choose Location</option>
</select>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
<script type="text/javascript">
(function($) {
$(document).ready(function(){
var firstSelect = $("#select1");
var secondSelect = $("#select2");
firstSelect.on("change", function(){
var main = $(this);
var mainName = main.val();
var mainCName = main.children('option:selected').attr("data-cname");
var arrCName = mainCName.split(", ");
var options2 = "<option value='0' selected >Choose Location</option>";
for(var i in arrCName){
options2 += "<option value='" + arrCName[i] + "' ";
options2 += "data-name='" + mainName + "'>" + arrCName[i] + "</option>\n";
}
secondSelect.html(options2);
});
});
})(jQuery);
</script>
</body>
</html>
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