laravel ->count() vs ->get()->count()

Question

Why are the two statement below behaving differentlY? The first returns 3 the second returns 1 for $progress. I thought that the first aggregates on the DB and the second on the server. So they should still return the same value.

$progress = $this->user->userActivities()->select('date')
                ->groupBy('date')
                ->get()->count();

$progress =  $this->user->userActivities()->select('date')
                ->groupBy('date')
                ->count();

Solution 1

->get()->count() will load Eloquent model objects into memory and then will count those.

->count() will use DB aggregate function, so it will definitely be more efficient:

select count(*) as aggregate ...

Solution 2

It's quite late answer but I had faced the same issue. These two examples are returning two different counts because of groupBy you have used.

$progress = $this->user->userActivities()->select('date')
            ->groupBy('date')
            ->get()->count();

This takes the rows first, then count the row numbers and returns the count.

$progress =  $this->user->userActivities()->select('date')
            ->groupBy('date')
            ->count();

Whereas this counts the rows by its group in the DB and returns the first group's row record count only from the list.

the solution I used instead of get()->count() for my case is like

$progress =  $this->user->userActivities()
            ->distinct('date')
            ->count('date');

Solution 3

Use ->get()->count() is wrong. I used ->get()->count() in my web app and when my database records have more than 80000 records I get error 500 in my app.

Solution 4

$count = Model::all()->count();
return view('home',compact('count'));

this will function for laravel 6;

Solution 5

The first counts the number of returned records, the second counts the records and returns the number. If you are using a paging of 10, for example, then the first will yield 10 and the second the actual number if the number of mathcing elements is greater than 10.

View more solutions

Comments

[Vytenis Ščiukas]

Not the same, one ->count() gets database count (COUNT) and ->get()->count() returns collection count. Most of the time they return the same number, but functionally they are not the same.