Php 从多维数组中删除所有重复数据_Php_Multidimensional Array_Duplicates_Filtering

Php 从多维数组中删除所有重复数据

php

Php 从多维数组中删除所有重复数据,php,multidimensional-array,duplicates,filtering,Php,Multidimensional Array,Duplicates,Filtering,我试图删除所有重复编号的键，我尝试了一些在这里发布的解决方案，比如我在脚本中使用的解决方案，但都没有达到我的目的这是我的阵列：至少有4个卡ID重复 Array ( [0] => Array ( [id_card] => 11883834 [type] => 1 [registed] => 1547610891 ) [1] => Array

我试图删除所有重复编号的键，我尝试了一些在这里发布的解决方案，比如我在脚本中使用的解决方案，但都没有达到我的目的

这是我的阵列：

至少有4个卡ID重复

Array
(
    [0] => Array
        (
            [id_card] => 11883834
            [type] => 1
            [registed] => 1547610891
        )

    [1] => Array
        (
            [id_card] => 20311077
            [type] => 1
            [registed] => 1547610891
        )

    [2] => Array
        (
            [id_card] => 16187903
            [type] => 3
            [registed] => 1547610891
        )

    [3] => Array
        (
            [id_card] => 16354099
            [type] => 1
            [registed] => 1547610891
        )

    [4] => Array
        (
            [id_card] => 21133393
            [type] => 4
            [registed] => 1547610891
        )

    [5] => Array
        (
            [id_card] => 15452852
            [type] => 2
            [registed] => 1547610891
        )

    [6] => Array
        (
            [id_card] => 19775869
            [type] => 2
            [registed] => 1547610891
        )

    [7] => Array
        (
            [id_card] => 20311077
            [type] => 1
            [registed] => 1547610891
        )

    [8] => Array
        (
            [id_card] => 21133393
            [type] => 4
            [registed] => 1547610891
        )

    [9] => Array
        (
            [id_card] => 11883834
            [type] => 1
            [registed] => 1547610891
        )

)
1

目前我有这样的想法：

<?php
$array_data = array_map('unserialize', array_unique(array_map('serialize', $myArray)));
echo '<pre>';
print_r($array_data);
echo '</pre>';
?>

$array = [
    ['id_card' => 11883834, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 20311077, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 16187903, 'type' => 3, 'registed' => 1547610891],
    ['id_card' => 16354099, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 21133393, 'type' => 4, 'registed' => 1547610891],
    ['id_card' => 15452852, 'type' => 2, 'registed' => 1547610891],
    ['id_card' => 19775869, 'type' => 2, 'registed' => 1547610891],
    ['id_card' => 20311077, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 21133393, 'type' => 4, 'registed' => 1547610891],
    ['id_card' => 11883834, 'type' => 1, 'registed' => 1547610891]
];

var_export(array_values(array_column(array_reverse($array), null, 'id_card')));

只有10个键就可以很好地工作，但是当它使用50个或100个键时，就不再工作了

非常感谢您的帮助。

因此这里的问题是

数组\u unique

解决方案期望整个值是相等的-它们不只是根据您的ID字段进行比较

相反，您可能希望在数组中循环并跟踪您看到的ID，并且只获取您以前没有看到ID的元素

function filter_duplicate_field($data, $field) {
  $seen = array(); // To keep track of the keys we've seen
  $filtered = array(); // Will hold the result

  foreach($data as $item) {
    if(array_key_exists($item[$field], $seen)) {
      // We already encountered this key before.
      continue;
    }

    // Never-before seen key, append it to the result and set the key in $seen
    $filtered[] = $item;
    $seen[$item[$field]] = TRUE;
  }

  return $filtered;
}

请注意，这使用了PHP数组的映射形式，而不仅仅是将seed id附加到列表表单中，并使用类似于

in_array

的内容来检查我们是否看到了键。这对于性能来说很重要，特别是当我们要处理大型数据集时-

in_array

是O（n），带有数组中的#项，而

array_key_存在

是O（1）

此函数的更通用版本如下所示：

<?php
$array_data = array_map('unserialize', array_unique(array_map('serialize', $myArray)));
echo '<pre>';
print_r($array_data);
echo '</pre>';
?>

$array = [
    ['id_card' => 11883834, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 20311077, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 16187903, 'type' => 3, 'registed' => 1547610891],
    ['id_card' => 16354099, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 21133393, 'type' => 4, 'registed' => 1547610891],
    ['id_card' => 15452852, 'type' => 2, 'registed' => 1547610891],
    ['id_card' => 19775869, 'type' => 2, 'registed' => 1547610891],
    ['id_card' => 20311077, 'type' => 1, 'registed' => 1547610891],
    ['id_card' => 21133393, 'type' => 4, 'registed' => 1547610891],
    ['id_card' => 11883834, 'type' => 1, 'registed' => 1547610891]
];

var_export(array_values(array_column(array_reverse($array), null, 'id_card')));

然后您可以像这样调用它：

$result=filter\u duplicate\u field（$data，'id\u card'）