php remove duplicates from multidimensional array by value

Question

I would like to remove duplicates by value as you can see from the list_title. I know there are several questions and answers to this but their solution doesn\'

Answer 1

Just loop through the arrays and keep track of duplicate field entries.

Only the list_id and list_title will be considered for duplicate arrays but extra fields can be added. All the other keys are ignored.

 86,
        "list_reference" => 130948,
        "list_title" => "Offer:  apartment 2+kk",
        "list_city" => "Prague",
        "list_date" => "2017-03-03 11:20:35",
        "list_status" => 0,
        "list_creator" => "Company A",
        "list_price" => 30000,
        "list_furniture" => '""1","0","0""',
        "list_accommodation" => "flat"
    ],
    [
        "list_id" => 87,
        "list_reference" => 130947,
        "list_title" => "Offer:  apartment 2+kk", 
        "list_date" => "2017-03-03 11:20:35",
        "list_status" => 0,
        "list_creator" => "Company B",
        "list_price" => 30000,
        "list_furniture" => '""1","0","0""',
        "list_accommodation" => "flat"
    ]
];


$duplicateFields = ["list_id" => array(), "list_title" => array()];
foreach ($array as $index => $value) {
    if(in_array($value['list_id'], $duplicateFields['list_id']) || in_array($value['list_title'], $duplicateFields['list_title'])){
        unset($array[$index]);
    }else{
        array_push($duplicateFields['list_id'], $value['list_id']);
        array_push($duplicateFields['list_title'], $value['list_title']);
    }
}

var_dump($array);

Which yields:

array(1) {
  [0]=>
  array(10) {
    ["list_id"]=>
    int(86)
    ["list_reference"]=>
    int(130948)
    ["list_title"]=>
    string(22) "Offer:  apartment 2+kk"
    ["list_city"]=>
    string(6) "Prague"
    ["list_date"]=>
    string(19) "2017-03-03 11:20:35"
    ["list_status"]=>
    int(0)
    ["list_creator"]=>
    string(9) "Company A"
    ["list_price"]=>
    int(30000)
    ["list_furniture"]=>
    string(13) """1","0","0"""
    ["list_accommodation"]=>
    string(4) "flat"
  }
}