如何从 Laravel 的集合中计算不同的值？
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How to count distinct values from a collection in Laravel?
提问by Pathros
I have been struggling on how to get the quantity of distinct values from a collection in Eloquent.
我一直在努力研究如何从 Eloquent 的集合中获取不同值的数量。
I have been trying several methods, such as unique(), values(), etc., found on the docs. Even though there is indeed a count() method, there is no method to get the count of distinct values.
我一直在尝试在文档中找到的几种方法，例如 unique()、values() 等。即使确实有 count() 方法，也没有获取不同值计数的方法。
For example, by applying the following query
例如，通过应用以下查询
$technicalshighestdegrees = Capsule::table('academicinfo AS fa')
->selectRaw('DISTINCT fa.academic_id AS Id,c.name AS Degree')
->leftJoin('academics AS a','fa.academic_id','=','a.id')
->leftJoin('cat_degree AS c','fa.level','=','c.id')
->whereIn('a.type',['Technical'])
->where('a.status','!=','Retired')
->where('c.degree',true)
->orderBy('a.id')
->orderBy('c.hierarchy','desc')/*http://stackoverflow.com/a/17006377/1883256*/
->get();
I get this collection:
我得到这个集合：
Illuminate\Support\Collection Object
(
[items:protected] => Array
(
[0] => stdClass Object
(
[Id] => 3
[Grado] => Master
)
[1] => stdClass Object
(
[Id] => 3
[Grado] => Bachelor
)
[2] => stdClass Object
(
[Id] => 4
[Grado] => Master
)
[3] => stdClass Object
(
[Id] => 4
[Grado] => Bachelor
)
[4] => stdClass Object
(
[Id] => 6
[Grado] => Master
)
[5] => stdClass Object
(
[Id] => 6
[Grado] => Bachelor
)
[6] => stdClass Object
(
[Id] => 18
[Grado] => Bachelor
)
[7] => stdClass Object
(
[Id] => 27
[Grado] => Bachelor
)
[8] => stdClass Object
(
[Id] => 34
[Grado] => Master
)
[9] => stdClass Object
(
[Id] => 34
[Grado] => Bachelor
)
[10] => stdClass Object
(
[Id] => 36
[Grado] => PhD
)
[11] => stdClass Object
(
[Id] => 36
[Grado] => Master
)
[12] => stdClass Object
(
[Id] => 36
[Grado] => Bachelor
)
[13] => stdClass Object
(
[Id] => 37
[Grado] => Bachelor
)
[14] => stdClass Object
(
[Id] => 42
[Grado] => PhD
)
[15] => stdClass Object
(
[Id] => 42
[Grado] => Master
)
[16] => stdClass Object
(
[Id] => 42
[Grado] => Bachelor
)
[17] => stdClass Object
(
[Id] => 50
[Grado] => Bachelor
)
[18] => stdClass Object
(
[Id] => 52
[Grado] => Bachelor
)
[19] => stdClass Object
(
[Id] => 53
[Grado] => Master
)
[20] => stdClass Object
(
[Id] => 53
[Grado] => Bachelor
)
[21] => stdClass Object
(
[Id] => 54
[Grado] => Master
)
[22] => stdClass Object
(
[Id] => 54
[Grado] => Bachelor
)
[23] => stdClass Object
(
[Id] => 55
[Grado] => Master
)
[24] => stdClass Object
(
[Id] => 55
[Grado] => Bachelor
)
[25] => stdClass Object
(
[Id] => 57
[Grado] => Bachelor
)
[26] => stdClass Object
(
[Id] => 68
[Grado] => Master
)
[27] => stdClass Object
(
[Id] => 68
[Grado] => Bachelor
)
[28] => stdClass Object
(
[Id] => 72
[Grado] => Master
)
[29] => stdClass Object
(
[Id] => 72
[Grado] => Bachelor
)
[30] => stdClass Object
(
[Id] => 77
[Grado] => Bachelor
)
[31] => stdClass Object
(
[Id] => 82
[Grado] => Bachelor
)
[32] => stdClass Object
(
[Id] => 85
[Grado] => PhD
)
[33] => stdClass Object
(
[Id] => 85
[Grado] => Master
)
[34] => stdClass Object
(
[Id] => 85
[Grado] => Bachelor
)
[35] => stdClass Object
(
[Id] => 92
[Grado] => Master
)
[36] => stdClass Object
(
[Id] => 92
[Grado] => Bachelor
)
[37] => stdClass Object
(
[Id] => 100
[Grado] => Master
)
[38] => stdClass Object
(
[Id] => 100
[Grado] => Bachelor
)
[39] => stdClass Object
(
[Id] => 111
[Grado] => Bachelor
)
[40] => stdClass Object
(
[Id] => 117
[Grado] => Master
)
[41] => stdClass Object
(
[Id] => 117
[Grado] => Bachelor
)
[42] => stdClass Object
(
[Id] => 123
[Grado] => Master
)
[43] => stdClass Object
(
[Id] => 123
[Grado] => Bachelor
)
)
)
Since, I just want to get the highest degrees (a user Id may have several historical degrees), I apply the unique() method, that according to the docs, it leaves only the first original value, in my case, I have already ordered them by hierarchy desc:
因为，我只想获得最高学位（一个用户 ID 可能有几个历史学位），所以我应用了 unique() 方法，根据文档，它只留下第一个原始值，就我而言，我已经按层次结构对它们进行排序：
$technicalshighestdegrees = $technicalshighestdegrees->unique('Id');
And now I get the following collection (reduced to 25 items, which is exactly the total number):
现在我得到以下集合（减少到 25 个项目，这正是总数）：
Illuminate\Support\Collection Object
(
[items:protected] => Array
(
[0] => stdClass Object
(
[Id] => 3
[Degree] => Master
)
[2] => stdClass Object
(
[Id] => 4
[Degree] => Master
)
[4] => stdClass Object
(
[Id] => 6
[Degree] => Master
)
[6] => stdClass Object
(
[Id] => 18
[Degree] => Bachelor
)
[7] => stdClass Object
(
[Id] => 27
[Degree] => Bachelor
)
[8] => stdClass Object
(
[Id] => 34
[Degree] => Master
)
[10] => stdClass Object
(
[Id] => 36
[Degree] => PhD
)
[13] => stdClass Object
(
[Id] => 37
[Degree] => Bachelor
)
[14] => stdClass Object
(
[Id] => 42
[Degree] => PhD
)
[17] => stdClass Object
(
[Id] => 50
[Degree] => Bachelor
)
[18] => stdClass Object
(
[Id] => 52
[Degree] => Bachelor
)
[19] => stdClass Object
(
[Id] => 53
[Degree] => Master
)
[21] => stdClass Object
(
[Id] => 54
[Degree] => Master
)
[23] => stdClass Object
(
[Id] => 55
[Degree] => Master
)
[25] => stdClass Object
(
[Id] => 57
[Degree] => Bachelor
)
[26] => stdClass Object
(
[Id] => 68
[Degree] => Master
)
[28] => stdClass Object
(
[Id] => 72
[Degree] => Master
)
[30] => stdClass Object
(
[Id] => 77
[Degree] => Bachelor
)
[31] => stdClass Object
(
[Id] => 82
[Degree] => Bachelor
)
[32] => stdClass Object
(
[Id] => 85
[Degree] => PhD
)
[35] => stdClass Object
(
[Id] => 92
[Degree] => Master
)
[37] => stdClass Object
(
[Id] => 100
[Degree] => Master
)
[39] => stdClass Object
(
[Id] => 111
[Degree] => Bachelor
)
[40] => stdClass Object
(
[Id] => 117
[Degree] => Master
)
[42] => stdClass Object
(
[Id] => 123
[Degree] => Master
)
)
)
What I want is to get the quantities for each distinct degree value as follows:
我想要的是获得每个不同程度值的数量，如下所示：
Array
(
[Master] => 13
[Bachelor] => 9
[PhD] => 3
)
But in an Eloquent collection...
但是在 Eloquent 集合中...
How can I achieve this?
我怎样才能做到这一点？
回答by Jarek Tkaczyk
If you really want to do that using collection methods, then here it goes:
如果你真的想使用收集方法来做到这一点，那么这里是：
$degrees->groupBy('Degree')->map(function ($people) {
return $people->count();
});
// Collection {
// 'Master' => 13,
// 'Bachelor' => 9,
// 'PhD' => 3
// }
回答by DIGITALCRIMINAL
Could also do the following:
还可以执行以下操作：
$master = $degrees->sum('Master');
return $master;
$bachelor = $degrees->sum('Bachelor');
return $bachelor;
$phD = $degrees->sum('PhD');
return $phD;
