How to find duplicate value in sample array

Question

How to find duplicate value in sample array using php

Array
(
    [id] => 644
    [qty] => 1
    [product] => 127
    [super_attribute] => Array
        (
            [140] => 16
        )

)
Array
(
    [id] => 648
    [qty] => 1
    [product] => 111
    [super_attribute] => Array
        (
            [140] => 18
        )

)
Array
(
    [id] => 652
    [qty] => 1
    [product] => 111
    [super_attribute] => Array
        (
            [140] => 18
        )

)

in this above array i want to find duplicate [product] => 111 and [140] => 18 . How can i achieve this?

Answer 1

One possible way to do this is to combine the two elements you're looking for into one longer key, then create a two-dimensional array listing all the IDs that have the new key.

In the code below I have multiplied the product number by 1000, added the value of super_attribute[140] and cast the result to a string. There are other ways you might obtain a new key depending on what you know about the data you're working with.

<?php
$arr  = [
    [

    "id" => 644,
    "qty" => 1,
    "product" => 127,
    "super_attribute" => [
        "140" => 16
        ]
    ],

    [
    "id" => 648,
    "qty" => 1,
    "product" => 111,
    "super_attribute" => [
        "140" => 18
        ]
    ],
    [
        "id" => 652,
        "qty" => 1,
        "product" => 111,
        "super_attribute" => [
            "140" => 18
        ]
    ]
];

$dup = [];

foreach($arr as $subArr) {
    // Calculate the new combined key
    $newKey = (string)($subArr['product']*10000+$subArr["super_attribute"][140]);

    // If we don't have this new key, create an array with the ID,
    // otherwise, add the ID to the existing array for the new key.
    if (isset($dup[$newKey])) {
        $dup[$newKey][] = $subArr['id'];
    } else {
        $dup[$newKey] = [$subArr['id']];
    }
}

var_dump($dup);

Output:

array (size=2)
  1270016 => 
    array (size=1)
      0 => int 644
  1110018 => 
    array (size=2)    //IDs with the combined key 111 and 18
      0 => int 648    
      1 => int 652