Laravel select specific columns with Eloquent while eager loading

Question

I'm using Laravel 8. I have 2 tables and trying to select specific columns from both tables using Eloquent:

$ids = [1, 8, 14];
$food = Food::with(
            ['animals' => function ($query)
            {
                $query->select('id', 'name');
                $query->where('status', 1);
            }])
            ->select('id', 'type')
            ->whereIn('id', $ids)
            ->where('status', 1)
            ->get();

However, if I add a select method to the Food model, Laravel returns null for the animals table.

If I don't specify selects on the Food model, Laravel returns everything from the Food model and id, name from the animals table.

How can I select both from the Food and the Animal table simultaneously, while using Eager Loading?

you have to make sure to also select any foreign keys needed for the relationship — lagbox, Oct 06 '20 at 18:54
@lagbox This was the problem, thank you so much for pointing it out. I left out one of the foreign keys from the select query! If you create an answer, I'll approve it! — Radical_Activity, Oct 06 '20 at 20:13
@lagbox The `animals` table. I added it to the `food` table's select and it worked instantly. — Radical_Activity, Oct 07 '20 at 10:53

score 3 · Accepted Answer · answered Oct 06 '20 at 20:17

3

You have to make sure you are selecting the id's and any foreign keys that would be needed for the relationship from either side of that relationship. This allows Eloquent to match up parents to their children.

answered Oct 06 '20 at 20:17

lagbox

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score 0 · Answer 2 · answered Aug 01 '23 at 12:57

lagbox's suggestion actually pointed me in the direction of the solution to my issue, which was similar to the original issue. I also had a query with a select-statement and was trying to eager load a relationship. In my case the problem lay with aliasing the id that was needed to load the relationship.

So originally my code looked like this: Question::query()->select(['questions.id AS question_id', [...])->with('translations')->get(). It was actually the "AS question_id" part that led to the relationship data turning up as empty arrays. Once I deleted that alias and selected it as just 'questions.id', the relationship data could be retrieved again.

score -1 · Answer 3 · answered Oct 06 '20 at 19:36

Try this one, specify the table in select.

Food::with(['animals' => function ($query) {
            $query->where('status', 1);
        }])
        ->select('food.id', 'animals.type', 'food.type')
        ->whereIn('id', $ids)
        ->where('status', 1)
        ->get();

Laravel select specific columns with Eloquent while eager loading

3 Answers3

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