ManyToMany with and whereIn - laravel

I have a ManyToMany relationship between AdInterest and AdInterestGroup models, with a belongsToMany() method in each model so I can use dynamic properties:
AdInterest->groups
AdInterestGroup->interests
I can find all the "interests" in a single group like this:
$interests = AdInterestGroup::find(1)->interests->pluck('foo');
What I need is a merged, deduplicated array of the related 'foo' field from multiple groups.
I imagine I can deduplicate with ->unique(), but first, as you'd expect, this:
AdInterestGroup::whereIn('id',[1,2])->interests->get();
throws:
Property [interests] does not exist on the Eloquent builder instance.
The advice seems to be to use eager loading via with():
AdInterestGroup::with('interests')->whereIn('id',[1,2])->get();
Firstly, as you'd expect that's giving me an array of two values though (one for each ID).
Also, if I try and pluck('foo') again, it's looking in the wrong database table: from the AdInterestGroup table, rather than the relationship (AdInterest).
Is there a nice, neat Collection method / pipeline I can use to combine the data and get access to the relationship fields?

Use pluck() and flatten():
$groups = AdInterestGroup::with('interests')->whereIn('id', [1, 2])->get();
$interests = $groups->pluck('interests')->flatten();
$foos = $interests->pluck('foo')->unique();

Related

How to combine three many to many relationship results in a single collection in Laravel?

I have a many to many relationship between the following:
actor <-> theater_play, actor <-> musical, actor <-> ballet_play
How can I make a single array to display all the results from these relationships in Laravel?
I have now:
$actor->theaterPlays, $actor->musicals, $actor->balletPlays
And I need to have something like this:
$actor->allPerformances
EDIT:
And I have to order theym by name, or by date of the performance etc.
Untested, however you should be able to create a new accessor within your Actor model which is responsible for merging all types together:
public function getAllPerformancesAttribute()
{
return $this->theaterPlays()
->get()
->merge($this->musicals()->get())
->merge($this->balletPlays()->get())
->all();
}

Laravel retrieve only specific fields from each item of collection

I may be missing something extremely trivial, but is it possible to retrieve specific columns/fields from models when grabbing a collection rather then returning the entire item's fields?
Here is my query:
$items = Items::where('visible', true)->take(10)->get();
This obviously returns each item in there entirety, including unique id's, and other fields i dont want to be fetched... how can i refine this query to just select specific fields from the models?
Laravel Query Builder get() function receives array of columns which you need to fetch.
$items = Items::where('visible', true)->take(10)->get(['column_1', 'column_2']);
Use select() method to do this:
$items = Items::select(['column_1', 'column_2']'])->where('visible', true)->take(10)->get();
Source: Latavel Database Query Builder
Laravel Query Builder gives a huge flexibility to write this types of query.
You can use select(), get(), all() methods.
Items::where('visible', true)->take(10)->get('col_1', 'col_2');
OR
Items::select('col_1', 'col_2')->where('visible', true)->take(10)->get();
Items::select(['col_1', 'col_2'])->where('visible', true)->take(10)->get();

Laravel, Many-to-many relationships, find() vs where()

I have a Laravel 4.2 site with a pretty simple database layout. The important part is a People model and a Subject model that have a many-to-many relationship. This works, so that, for instance:
$id = 5;
$ppl = Subject::find($id)->people()->orderBy('lastname')->get();
Returns all People for a given Subject. What I'm trying to do is instead of finding all the People for a single subject, to find all the people for multiple subjects. My guess was something like this:
$subjects = array(5, 6, 7);
$ppl = Subject::whereIn('id', $subjects)->people()->orderBy('lastname')->get();
That doesn't work (undefined method people()). Neither does the following (undefined property people):
$ppl = Subject::whereIn('id', $subjects)->people->orderBy('lastname')->get();
I'm currently just using raw SQL t get around this. How can I use eloquent relationships with where() or whereIn() calls on a model? Or, is there just a better eloquent way of approaching this problem.
Edit: Here's the raw SQL I used to get a list of the people.id's for a given array of subjects:
SELECT
DISTINCT(people.id)
FROM people
LEFT JOIN person_subject ON person_subject.person_id=people.id
WHERE
person_subject.subject_id IN (%s) AND
deleted_at IS NULL
Your eloquent relationships should allow you to eagar load the people related to a subject, you can do something like this:
Subject::whereIn('id', $subjects)->with('people')->orderBy('lastname')->get();
This will return your people related to the subjects.
Let me know if this doesn't work.
What you need is to join the tables to order by the lastname:
$ppl = Subject::whereIn('id', $subjects)
->select('subjects.*')
->distinct()
->join('people', 'people.id', '=', 'subjects.people_id')
->orderBy('lastname')
->get();
Check all your tables names because I don't know them and above are just an example one.

MINUS operation in Eloquent ORM

Is there any equivalent MINUS operation from SQL using Eloquent ORM?
For example
$model1 = Model::where('some constraints applied')
$model2 = Model::where('some constraints applied')
I want to get all models that exist in $model1 but not in $model2
seblaze's answer looks good, though it will run 3 queries. Another option is diff() method of the Collection object:
$result = $model1->diff($model2);
This works after fetching data from the db with 2 queries, but complete set of data (unless there are more depending on your 'constraints applied').
The easiest way i see it is :
//Get the id's of first model as array
$ids1 = $model1->lists('id');
//get the id's of second models as array
$ids2 = $model2->lists('id');
//get the models
$models = Model::whereIn('id',$ids1)->whereNotIn('id',$ids2)->get();
This is not tested code, please read more about eloquent queries here

return separate result for each relation in many to many

Hi i have a many to many relationship with the following structure:
services
apps
service_app
I would like to have an eloquent query to return a separate result for each relationship(basically the pivot table). I have the following :
$all = App::with('services')->get();
this will return an app with nested services, I would like to have this return a separate result for each app-service combination along with data from the pivot table. how is this possible using eloquent?
It's a bit strange, but it can easily be done if you don't think of the pivot table as a pivot table, but as an AppService.
So what you can do is create a model for it, probably named AppService. In that model, you would then have 2 belongsTo() relationships. One for App and one for Service.
Then you can query your pivot table directly and use those relationships to get what you need.
$appServices = AppService::all();
foreach($appServices as $appService) {
echo $appService->app->description;
echo $appService->service->description;
}

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