How to count distinct values from a collection in Laravel?

Question

I have been struggling on how to get the quantity of distinct values from a collection in Eloquent.

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.

For example, by applying the following query

$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:

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:

$technicalshighestdegrees = $technicalshighestdegrees->unique('Id');

And now I get the following collection (reduced to 25 items, which is exactly the total number):

What I want is to get the quantities for each distinct degree value as follows:

Array
(
    [Master] => 13
    [Bachelor] => 9
    [PhD] => 3
)

But in an Eloquent collection...

How can I achieve this?

Jarek Tkaczyk · Accepted Answer · 2021-01-23T10:14:11.723

24

Update for 2021/L6+

thanks @JeremyWadhams

$degrees->groupBy('Degree')->map(fn ($people) => $people->count());
// or using HigherOrder proxy on the collection
$degrees->groupBy('Degree')->map->count();

Using collection methods this would be it:

$degrees->groupBy('Degree')->map(function ($people) {
    return $people->count();
});

// Collection {
//   'Master' => 13,
//   'Bachelor' => 9,
//   'PhD' => 3
// }

edited Jan 23 '21 at 10:14

answered Mar 10 '16 at 19:08

Jarek Tkaczyk

78,987
25
159
157

1

I love this trick, thank you! You could simplify it one step more using the higher order map, like $degrees->groupBy('Degree')->map->count() – Jeremy Wadhams May 08 '20 at 20:14
Hello sir, Is there any way to count number of these unique groups ? in your example count should be 3 – Sagar Gautam Jan 22 '21 at 09:17
@SagarGautam `$degrees->groupBy(..)->count()` will do the trick – Jarek Tkaczyk Jan 23 '21 at 10:11
1

@JeremyWadhams a bit late on my part, but thanks for your comment! Feel free to EDIT existing answers with such improvements - I'm sure everyone will appreciate your effort! – Jarek Tkaczyk Jan 23 '21 at 10:18
@JarekTkaczyk count doesn;t work with group by ! – Sagar Gautam Jan 23 '21 at 13:04

score 10 · Answer 2 · answered Nov 21 '20 at 21:00

10

There is a Collection Helper called CountBy, does exactly what you need.

Collections CountBy

$degrees->countBy('Degree');

It will retourn as expected

 Array
(
    [Master] => 13
    [Bachelor] => 9
    [PhD] => 3
)

Simple :D

answered Nov 21 '20 at 21:00

Julio Popócatl

712
8
16

Too bad this was posted after the original accepted answer, this would be the best way to do it. – commadelimited Jan 13 '21 at 18:03

score -1 · Answer 3 · answered Jul 10 '17 at 11:33

-1

Could also do the following:

$master = $degrees->sum('Master');
return $master;

$bachelor = $degrees->sum('Bachelor');
return $bachelor;

$phD = $degrees->sum('PhD');
return $phD;

answered Jul 10 '17 at 11:33

PhoenixRebirthed

462
6
15

You are falling to de DRY principle – Julio Popócatl Feb 08 '21 at 01:37

How to count distinct values from a collection in Laravel?

3 Answers3