Laravel Eloquent: eager loading of multiple nested relationships

LaravelEloquentEager Loading

Laravel Problem Overview


What laravel says:

$books = App\Book::with('author.contacts')->get();

What I need is something like this

$books = App\Book::with('author[contacts,publishers]')->get();

where we eager load multiple relationships within a relationship.

Is this possible?

Laravel Solutions


Solution 1 - Laravel

You can do

 $books = App\Book::with('author.contacts','author.publishers')->get();

Solution 2 - Laravel

Laravel documentation on eager loading recommends listing the relationships in an array as follows:

$books = App\Book::with(['author.contacts', 'author.publishers'])->get();

You can have as many relationships as desired. You can also specify which columns should be included for a relationship like this:

//only id, name and email will be returned for author
//id must always be included
$books = App\Book::with(['author: id, name, email', 'author.contacts', 'author.publishers'])->get();

You may also add constrains as follows:

$books = App\Book::with(['author: id, name, email', 'author.contacts' => function ($query) {
                                          $query->where('address', 'like', '%city%');
                                     }, 'author.publishers'])->get();

Solution 3 - Laravel

So, now you can try

$books = App\Book::with(['author' => function($author){
     $author->with(['contacts', 'publishers'])->get();
}])->get();

Solution 4 - Laravel

When eager load nested relationships and we want to select just some columns and not all using relationship:id,name, always include the foreign key to the nested models, else they won't load at all.

Fort example, we have orders that have identities that have addresses.

This will not load the address:

User::orders()
    ->with('identity:id,name', 'identity.address:id,street')

This will load the address because we have supplied the address_id foreign key:

User::orders()
    ->with('identity:id,address_id,name', 'identity.address:id,street')

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionDrivingInsaneeView Question on Stackoverflow
Solution 1 - LaraveloseintowView Answer on Stackoverflow
Solution 2 - LaravelElisha SenooView Answer on Stackoverflow
Solution 3 - LaravelJonathan Omar MorenoView Answer on Stackoverflow
Solution 4 - LaravelChristos LytrasView Answer on Stackoverflow