Laravel eager relationships empty query - php

I have 3 tables : hotels, hotels_data, hotels_types
Table hotels have id, type, stars, etc... type field is set as foreign key referencing type_id in hotels_types. I'm managing to get the correct data from hotels_data but have an empty result on getting hotels_types title and I don't understand why.
The code is the following :
class Hotel extends Eloquent {
public function getList() {
$data = Hotel::select('id','stars')->with('HotelData', 'HotelType')->paginate(10);
return View::make('hotels.index')->with('hotels', $data);
}
public function HotelData()
{
return $this->hasOne('HotelsData')->select('id','hotel_id','title');
}
public function HotelType()
{
return $this->hasOne('HotelType','type_id', 'type')->select('id','type_id','title');
}
}

You're using the wrong relationship for HotelType()
Your Hotel model should use the inverse of hasOne, which is belongsTo, because it contains the foreign key to HotelType (when a table contains a foreign key, it always belongs to the table being pointed to).
The following should work:
public function hotelType() {
return $this->belongsTo('HotelType','type', 'type_id')->select('id','type_id','title');
}

I've obtained the desired result with the following:
Hotel::select('hotels.*','hotels_types.title as type')
->join('hotels_types', 'hotels.type', '=', 'hotels_types.type_id')
->with('HotelData');

Related

Laravel Eloquent getting data from relations

I have Task model. My Task model has some relationships and it currently looks like this:
class Task extends Model
{
use HasFactory;
public $timestamps = false;
public function city()
{
return $this->hasOne(City::class, 'id', 'city_id');
}
public function type()
{
return $this->hasOne(Type::class, 'id', 'type_id');
}
public function note()
{
return $this->hasOne(Note::class, 'id', 'note_id');
}
public function operator()
{
return $this->hasOne(User::class, 'id', 'operator_id');
}
}
Now, in my TasksController I need to get Tasks that match certain criteria, like this:
$tasks = Task::whereCityId($city->id)->whereTypeId($type->id)->get()->toArray();
The problem is that fields named city_id type_id note_id operator_id will get my integer values that they have.
Instead I would like to get certain value from a related Model.
For example:
operator_id should be replaced with username from User table that corresponds to the user id.
An obvious solution to this would be to simply use foreach loop, go through my results and get the data I need and simply create another array with the information replaced, but I am not sure if this is the best idea and perhaps there is something better.
You have to change in your code:
$this->hasOne(ClassName::class, 'id', 'foreign_key');
To
$this->belongsTo(ClassName::class, 'foreign_key', 'id');
because Task's id does not available as foreign key in these tables. These table's id present in task table as foreign key so you have to use belongsTo() relationship to tell script from where these id belongs.
Then access properties like this:
$tasks = Task::with("type", "city", "operator")
->whereCityId($city->id)->whereTypeId($type->id)->get();
foreach($tasks as $task){
echo $task->city->name;
}
first you should fix your relation:
public function city()
{
return $this->hasOne(City::class,'city_id','id');
}
and so one the same error, foreign key in argument order comes before the primary key.
after that you can use addSelect:
$tasks = Task::whereCityId($city->id)->whereTypeId($type->id)
->addSelect(['userName' => User::select('name')
->whereColumn('users.id', 'tasks.operator_id')
->limit(1)])->get()->toArray();
i think this will help better than what you ask.
$tasks = Task::whereCityId($city->id)
->whereTypeId($type->id)
->with('operator')
->get()->toArray();
with('operator') is ORM feature that make you collection to include its relation as collection property. In this case it will convert to array property.
you could access it from your foreach function as
#foreach($task as $key)
$key['operator']['username']
#endforeach
Have a nice day

How to create relationship between 3 models in laravel?

SQL scheme:
bulletins
id increment
deals
id increment
seller_id
buyer_id
deals_items - items = bulletins
id increment
title
desc
bulletin_id
deal_id
How can I get deal row by bulletin id? In raw SQL it looks like:
select `deals`.* from `deals` inner join `deals_items` on `deals_items`.`deal_id` = `deals`.`id` where `deals_items`.`bulletin_id` = 10572
I tried:
public function deals()
{
return $this->hasManyThrough(DealItem::class,Deal::class, 'bulletin_id','dealid','id');
}
But it seems a wrong way. Can't find right way in laravel doc about relation.
#HCK shows right way.
but when I doing $bulletin->deals() in blade template I got empty collection of deals.
When just $bulletin->deal - all is fine, we have collection of deals.
I using protected $with = ['deals'] in my bulletin model, but what is different call method or property? Why with method empty result?
#Amarnasan was close, but the order of the foreign keys was wrong. Try this:
Deal.php
public function bulletins()
{
return $this
->belongsToMany(Bulletin::class, 'deals_items', 'deal_id', 'bulletin_id')
->withPivot('title','desc');
}
Bulletin.php
public function deals()
{
return $this
->belongsToMany(Deal::class, 'deals_items', 'bulletin_id', 'deal_id')
->withPivot('title','desc');
}
From the docs:
As mentioned previously, to determine the table name of the
relationship's joining table, Eloquent will join the two related model
names in alphabetical order. However, you are free to override this
convention. You may do so by passing a second argument to the
belongsToMany method:
return $this->belongsToMany('App\Role', 'role_user');
In addition to customizing the name of the joining table, you may also
customize the column names of the keys on the table by passing
additional arguments to the belongsToMany method. The third argument
is the foreign key name of the model on which you are defining the
relationship, while the fourth argument is the foreign key name of the
model that you are joining to:
return $this->belongsToMany('App\Role', 'role_user', 'user_id', 'role_id');
Update
When you access the relationship as a method: $bulletin->deals() you are accessing the relationship itself. This will return an instance of \Illuminate\Database\Eloquent\Relations\BelongsToMany (in your case). Here the query is not executed yet, so you could keep adding constrains to your query, for example:
$bulletin
->deals()
->where('seller_id', 45) // <---
->skip(5) // <---
-> ... (And so on)
When you access it as a dynamic property, you are already executing the query, so this will return a Collection instance. Is the same as calling the relationship as a method and then attach the ->get() at the end, so this two are equivalent:
$bulletin->deals()->get()
// equals to:
$bulletin->deals
Check this other answer, it answers your question.
DealClass:
public function bulletins()
return $this->belongsToMany('App\Bulletin', 'deals_items ', 'bulletin_id', 'deal_id')->withPivot('title','desc');
}
BulletinClass:
public function deals()
return $this->belongsToMany('App\Deal', 'deals_items ', 'deal_id', 'bulletin_id')->withPivot('title','desc');
}
deals model -
public function bulletins()
return $this->belongsToMany(Bulletin::class, 'deals_items ', 'bulletin_id', 'deal_id');
}
bulletin model:-
public function deals()
{
return $this
->belongsToMany(Deal::class, 'deals_items', 'deal_id', 'bulletin_id',);
}

Multiple relationship between tables in Laravel 5.4

I have 3 tables (items, category_questions_mapping and category_questions) in mysql database in which I have the following columns:
items table has following columns:
item_id, uuid, radius, category_id
category_questions_mapping has following columns:
category_id, category_question_id
category_questions has following columns:
category_question_id, data
I have created the model for the items table which is Items.php in which I have created the following method:
public function category_questions() {
return $this->hasOne('App\CategoryQuestionsMapping','category_id','category_id');
}
The above method is basically a relationship between category_id of the items table with the category_id of category_question_mappings table
Problem Statement:
I am wondering what changes I should make in the above method so that I am able to pull data column value from category_questions table. Is there any we can make a relationship in the above method so that it can pull the data column ?
The above method will be used in the controller for display.
To acess the category_question table columns you must define the relationship on the category_question_mapping model too, like:
public function category_questions() {
return $this->hasOne('App\CategoryQuestions','category_question_id','category_question_id');
}
then acess the field you want like $items->category_questions_mapping->category_questions->data.
By the way, I'd recommend naming the first relationship you showed like category_questions_mapping() as it is linking with the category_questions_mapping table.
You can't change only the category_questions method to solve the problem. But you can make 2 relations in 2 models and query data through 2 relations.
// App\Item
public function category_questions_mapping() {
return $this->hasOne(CategoryQuestionsMapping::class, 'category_id', 'category_id');
}
// App\CategoryQuestionsMapping
public function category_question() {
return $this->hasOne(CategoryQuestion::class, 'category_question_id', 'category_question_id');
}
// Somewhere else
// Get data:
$data = $item->category_questions_mapping->category_question->data;
// Find by data:
$items = \App\Item
::whereHas('category_questions_mapping.category_question', function ($query) {
$query->where('data', 'foo');
})
->get();
Your relationship use like this :
public function category_questions() {
return $this->belongsToMany('App\CategoryQuestions','category_questions_mapping','category_id', 'category_question_id);
}

Get filtered rows from a table and its pivot table using eloquent in laravel 5.6

I have two models Base_voter and Custom_list
Custom_list.php
public function base_voters()
{
return $this->hasMany('App\Models\Base_voter', 'custom_pivot_base', 'custom_list_id', 'base_voter_id');
}
Base_voter
public function custom_lists()
{
return $this->belongsToMany('App\Models\Custom_list', 'custom_pivot_base', 'custom_list_id', 'base_voter_id');
}
There is pivot table custom_pivot_base with two columns
custom_list_id, base_voter_id
Now, I need to retrieve base_voter lists whose customer_list_id = 1 and street = $street, where city = $city. These address and city column are in base_voters table. How can I do this with eloquent in laravel
Change your relationship in Custom_list Model
public function base_voters()
{
return $this->belongsToMany('App\Models\Base_voter', 'custom_pivot_base', 'custom_list_id', 'base_voter_id');
}
Also change your relationship in Base_voter Model
public function custom_lists()
{
return $this->belongsToMany('App\Models\Custom_list', 'custom_pivot_base', 'base_voter_id', 'custom_list_id');
}
You need to fetch base_voter lists for customer_list_id = 1 that means fetch customer_list by id 1 and then fetch its related base_voters. Like this
$customList = Custom_list::with(['base_voters' => function($query) use ($city, $gender){
$query->where('city',$city)->where('gender', $gender);
}])->find(1);
Now you can print it like this
print_r($customList->base_voters);
What u are looking for is "hasManyThrough" relationship.
https://laravel.com/docs/5.6/eloquent-relationships#has-many-through
Please go through this documentation and define the relationship between your models.

Retrieving a single colum from a pivot table - Laravel 5

I am using a pivot table genre_user to relate user to genre.
table contains the following fields
id
user_id
genre_id
Following are the model definitions
User.php
public function genres() {
return $this->belongsToMany('App\Genre');
}
Genre.php
public function artists() {
return $this->belongsToMany('App\User');
}
I am getting the results as a collection when I use the following code
$user = auth()->user();
dd($user->genres);
I want to show the selected genres in a dropdown field of genres. Is it possible to get only the current users genre_id as an array from the pivot table without using a foreach loop.
I think what will help you achieve this behavior is the lists() method.
Try something like
$user_genres = auth()->user()->genres()->lists('name','id');
If you are using Forms & HTML package you can just do
{!! Form::select('genres',$user_genres,null) !!}
And here is your dropdown
More info here (scroll down to "Retrieving A List Of Column Values")
A user should have one genre.
Therefore, your models should contain the following relations:
User.php
public function genre() {
return $this->hasOne('App\Genre');
}
Genre.php
public function artists() {
return $this->belongsToMany('App\User');
}

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