php按值从多维数组中删除重复项

Question

我想从中删除重复值,如您所见list_title.我知道有几个问题和答案,但他们的解决方案对我不起作用.

这是我尝试过的:

$uniqueArray = array_map("unserialize", array_unique(array_map("serialize", $notify)));

结果:

Array
(
[0] => Array
    (
        [list_id] => 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
    )

[1] => Array
    (
        [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
    )

[2] => Array ...

由于标题,预期结果应该是其中之一:

Array
(
[0] => Array
(
    [list_id] => 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
)

Answer 1

因此，基本上，您想按'list_title'列删除重复项。假设我们保留该标题的第一次出现。然后，您可以使用几个标准函数来实现此目的：

// Reverse array, so the first occurrence kept.
$data = array_reverse($data);

$result = array_reverse( // Reverse array to the initial order.
    array_values( // Get rid of string keys (make array indexed again).
        array_combine( // Create array taking keys from column and values from the base array.
            array_column($data, 'list_title'), 
            $data
        )
    )
);

这是工作演示。

更新：

基于@mickmackusa注释，可以将代码简化为：

$result = array_reverse(array_values(array_column(
    array_reverse($data),
    null,
    'list_title'
)));

在文档中有关column_key参数规格的说明如下：

返回完整的数组或对象也可能为NULL（这与index_key一起用于重新索引数组很有用）。

Answer 2

谢谢大家，有时过度思考会影响常识。

我只是从 MYSQL 查询中解决了它，例如：

 GROUP BY list_title ORDER BY list_date