Let's say I have three tables:
Article: id, ...
Advert: id, display_on_every_subsite, ...
Article_Advert: advert_id, article_id
I have a simply Eloquent's relationship: belongsToMany between Article and Advert - Article_Advert is the pivot table.
The problem is that I need to fetch all Adverts for specified Article(s) AND all Adverts with display_on_every_subsite = 1.
I'm trying to achieve this using unions, this is what I've at this moment:
$this->belongsToMany('Advert', 'Article_Advert', 'article_id', 'advert_id')->union(Advert::allSubpages()->selectRaw('`advert`.*, `advert`.`id` as `pivot_advert_id`, null as `pivot_article_id`')->getQuery());
The problem is that when pivot_article_id is null, Eloquent does not attach fetched rows to any related model.
It's almost like that, just change the following:
// I assume you have this inside Article Model
$articleId = $this->id;
$this->belongsToMany('Advert', 'Article_Advert', 'article_id', 'advert_id')
->union(Advert::allSubpages()
->selectRaw("`advert`.*, `advert`.`id` as `pivot_advert_id`, '$articleId' as `pivot_article_id`")
->where('display_on_every_subsite','=','1')
->getQuery());
Related
Say I have the following tables:
event_relationships
id
user_id
relationship
primary_event_id
secondary_event_id
events
id
user_id
name
color
In my user model, I have my relationship setup like:
$this->hasMany(EventRelationships::class, 'user_id');
And each event relationship belongs to one user.
How can I use Laravel Eloquent to get a list of all the event relationships, but also get each event's name and color? Matching on the primary_event_id and secondary_event_id.
Is this possible with one query?
In pure eloquent, in the laravel way, that would be :
$eventRelationships = EventRelationships::with('primaryEvent', 'secondaryEvent')->get();
foreach($eventRelationships as $eventRelationship){
$primary_event_name = $eventRelationship->primaryEvent->name;
$secondary_event_name = $eventRelationship->secondaryEvent->name;
}
but it's in 2 queries. If you want only one query, you have to use a join :
$eventRelationships = EventRelationships::query()
->join('events as primary_events', 'events.id', 'event_relationships.primary_event_id')
->join('events as secondary_events', 'events.id', 'event_relationships.secondary_event_id')
->select('event_relationships.*', 'primary_events.name as primary_event_name', 'secondary_events.name as secondary_event_name')
->get();
foreach($eventRelationships as $eventRelationship){
$primary_event_name = $eventRelationship->primary_event_name;
$secondary_event_name = $eventRelationship->secondary_event_name;
}
It might be easier to use the first one as you manipulate eloquent object
In my application, I have a posts table, categories tables and category_post table as a post and category have a many to many relationship.
I want to get all posts with their attached categories, but also group them together as on my frontend I want to be a loop over an object and show a list like this,
Cooking
Post Number 1
Post Number 3
Post Number 4
Music
Post Number 2
Post Number 5
Languages
Post Number 6
Post Number 7
I know in my controller I can do this,
$posts = Post::with('categories')->get();
But I don't how to groupBy a relational attribute or if I can structure the returned data in such a way that I can loop over it to form the list below.
you can get the data from db and then group them the way you want:
$posts = Post::with('categories')->get();
$result = $posts->groupBy([
'categories',
function ($item) {
return $item['category_name'];
},
], $preserveKeys = true);
more details about grouping by relation fields in:
https://laravel.com/docs/7.x/collections#method-groupby
As per given your table: posts and categories tables are the main tables and category_post table is a pivot table which contains the relation between posts and categories table :
So, Your relation should be posts->category_post->categories
$posts = Posts::with('category_post')->get();
$grouped = $posts->groupBy('category_post.category_id');
The category_post also related to the categories table for categories data.
In category model you cam setup and belongsToMany relation like the following
function posts()
{
return $this->beongsToMany(Post::class, 'category_post', 'category_id', 'post_id');
}
Then do as Arun A S suggested.
There are 3 models:
First (first_id)
Connection (connection_id, first_id, product_id)
Second (second_id, product_id)
I would like to connect the three models together using laravel relationships
First->joined to Connection though first_id
Connection->joined to First through first_id, & joined to Second through product_id
Second -> joined to Connection through product_id
So: First joined to Second through Connection first_id, product_id
Is this possible to do using something like HasManyThrough?
Thanks for your time
On your First model:
public function second () {
return $this->hasManyThrough(
Second::class,
Connection::class,
'product_id', // Foreign key on connection table
'product_id', // Foreign key on second table
'first_id', // Local key on first table
'first_id' // Local key on connection table
);
}
Based on your description the column names should work.
In tinker you can validate if it's hooked up correctly by doing something like First::first()->second.
It depends on what type of relationship Your first model and second model shares as well as what type of relation second and third model shares.
if consider your first model First and second model Second shares a one-to-one relation, as well as Second model and Third models shares one-to-one relationships.
It will be $first->second->third; //no has many through relationship requires
If your First model and Second models shares as hasMany-belongs to relation than you need to use hasManyThrough relationship
example from doc
class Country extends Model
{
public function posts()
{
return $this->hasManyThrough(
'App\Post',
'App\User',
'country_id', // Foreign key on users table...
'user_id', // Foreign key on posts table...
'id', // Local key on countries table...
'id' // Local key on users table...
);
}
}
You can try using nested relationships.
Nested Eager Loading
To eager load nested relationships, you may use "dot" syntax. For example, let's eager load all of the book's authors and all of the author's personal contacts in one Eloquent statement:
$books = App\Book::with('author.contacts')->get();
Book Model:
public function author()
{
return $this->hasOne('App\Author');
}
Author Model:
public function contacts()
{
return $this->hasMany('App\Author');
}
Documentation:
https://laravel.com/docs/5.8/eloquent-relationships
i'm trying to get all the lead_id inside my pivot table but i can't make it work.
controller:
$levels = Level::all();
$levels->lead()->attach('lead_id');
return $levels;
Model Level:
public function lead(){
return $this->belongsToMany(Lead::class, 'level_students')->withPivot('level_id', 'lead_id');
}
Model Lead:
public function level(){
return $this->belongsToMany(Level::class, 'level_students')->withPivot( 'lead_id', 'level_id');
}
If you mean all lead_id of a Level, then you can use pluck().
$level->lead->pluck('lead_id');
I'm not really sure what you are trying to achieve because it seems that you want to retrieve all lead_id associated with any Level. But if that is the case, then you can create a model for the pivot table (e.g. LevelLead) and use distinct() or with Query Builder:
$leadIds = DB::table('level_students')->select('lead_id')->distinct()->get();
If you want to get the referenced table's column (e.g. leads table's name column) then you can use JOIN. Check Laravel's doc for more options. For example, assuming the table name for Lead is leads, then:
$leads = DB::table('level_students')->join('leads', 'level_students.lead_id', '=', 'leads.lead_id')->select('level_students.lead_id', 'leads.name')->distinct()->get();
I have a Pivot table thats used to join two other tables that have many relations per hotel_id. Is there a way I can eagerload the relationship that pulls the results for both tables in one relationship? The raw SQL query, works correctly but when using belongsToMany the order is off.
Amenities Pivot Table
id
hotel_id
distance_id
type_id
Distance Table
id
name
Type Table
id
name
RAW Query (This works fine)
SELECT * FROM amenities a
LEFT JOIN distance d ON a.distance_id = d.id
LEFT JOIN type t ON a.type_id = t.id WHERE a.hotel_id = ?
My "Hotels" Model is using belongsToMany like so
public function distance() {
return $this->belongsToMany('Distance', 'amenities', 'hotel_id', 'distance_id');
}
public function type() {
return $this->belongsToMany('Type', 'amenities', 'hotel_id', 'type_id');
}
This outputs the collection, but they are not grouped correctly. I need to loop these into select fields side by side as entered in the pivot table, so a user can select a "type" and the "distance", but the order is off when using the collection. The raw query above outputs correctly.
Hotels::where('id','=','200')->with('distance', 'type')->take(5)->get();
Ok Solved it. So apparently you can use orderBy on your pivot table. Incase anyone else has this issue this is what I did on both relationships.
public function distance() {
return $this->belongsToMany('Distance', 'amenities', 'hotel_id', 'distance_id')->withPivot('id')->orderBy('pivot_id','desc');
}
public function type() {
return $this->belongsToMany('Type', 'amenities', 'hotel_id', 'type_id')->withPivot('id')->orderBy('pivot_id','desc');
}
It's not really a great practice to include other query building steps in the relationship methods on your models. The relationship method should just define the relationship, nothing else. A cleaner method is to apply eager load constraints. (scroll down a bit) Consider the following.
Hotels::where('id', 200)->with(array(
'distance' => function ($query)
{
$query->withPivot('id')->orderBy('pivot_id','desc');
},
'type' => function ($query)
{
$query->withPivot('id')->orderBy('pivot_id','desc');
},
))->take(5)->get();
If you find that you are eagerly loading this relationship in this way often, consider using scopes to keep things DRY. The end result will allow you to do something like this.
Hotels::where('id', 200)->withOrderedDistance()->withOrderedType()->take(5)->get();
P.S. Your models should be singular. Hotel, not Hotels. The model represents a single record.
Solved by using ->withPivot('id')->orderBy('pivot_id','desc');
Posted answer in the question.