Good day to you all...
I'm trying to access a collection based on a column in a related table within Eloquent (Laravel 4.2).
I have the following tables:
tags:
(int) id
(string) name
tag_usage:
(int) id
(string) model (the name of the model that is allowed to use the tag)
tag_tag_usage: (pivot)
(int) id
(int) tag_id
(int) tag_usage_id
I also have a taggables (polymorphic to store tags for multiple models) table which I believe is out of scope here as I only want to retrieve the tags that am allowed to use for each model.
My tag model has the relationship
public function usage()
{
return $this->belongsToMany('TagUsage');
}
and the TagUsage model has
public function tags() {
return $this->belongsToMany('Tag');
}
Now, what I want to do is return the tags that ONLY have a specific usage, some pseudo code would be
get_tags->where(tag_usage.model = modelname)
which would return only a subset of the tags.
Tried a few things with no success so over to the many fine brains available here.
Many thanks.
You need to use whereHas in the following way:
$tags = Tag::whereHas('usage', function($q)
{
$q->whereModel('modelname');
})->get();
Related
I'm new to Laravel. I am developing a project. and in this project I have 4 tables related to each other
-Users
-Orders
-OrderParcels
-Situations
When listing the parcels of an order, I want to get the information of that order only once, the user information of that order once again, and list the parcels as a table under it. so far everything ok. but I also want to display the status of the parcels listed in the table as names. I couldn't add the 4th table to the query. do you have a suggestion? I'm putting pictures that explain the structure below.
My current working code is
$orderParcels = Orders::whereId($id)
->with('parcels')
->with('users:id,name')
->first();
and my 'orders' model has method
public function parcels(){
return $this->hasMany(OrderParcels::class);
}
public function users(){
return $this->hasOne(User::class,'id','affixer_id');
}
Note[edit]: I already know how to connect like this
$orderParcels = DB::table('order_parcels as op')
->leftjoin('orders as o','op.orders_id','o.id')
->leftjoin('users as u','o.affixer_id','u.id')
->leftjoin('situations as s','op.status','s.id')
->select('op.*','o.*','u.name','s.situations_name')
->where('op.orders_id',$id)->get();
but this is not working for me, for each parcels record it returns me orders and user info. I want once orders info and once user info.
Laravel provides an elegant way to manage relations between models. In your situation, the first step is to create all relations described in your schema :
1. Model Order
class User extends Model {
public function parcels()
{
return $this->hasMany(OrderParcels::class);
}
public function users()
{
return $this->hasOne(User::class,'id','affixer_id');
}
}
2. Model Parcel
class Parcel extends Model {
public function situations()
{
return $this->hasOne(Situation::class, ...);
}
}
Then, you can retrieve all desired informations simply like this :
// Retrieve all users of an order
$users = $order->users; // You get a Collection of User instances
// Retrieve all parcels of an order
$parcels = $order->parcels; // You get a Collection of User instances
// Retrieve the situation for a parcel
$situations = $parcel->situations // You get Situation instance
How it works ?
When you add a relation on your model, you can retrieve the result of this relation by using the property with the same name of the method. Laravel will automatically provide you those properties ! (e.g: parcels() method in your Order Model will generate $order->parcels property.
To finish, in this situation where you have nested relations (as describe in your schema), you should use with() method of your model to eager load all the nested relation of order model like this :
$orders = Orders::with(['users', 'parcels', 'parcels.situations'])->find($id)
I encourage you to read those stubs of Laravel documentation :
Define model relations
Eager loading
Laravel Collection
Good luck !
Use join to make a perfect relations between tables.
$output = Orders::join('users', 'users.id', '=', 'orders.user_id')
->join('order_parcels', 'order_parcels.id', '=', 'orders.parcel_id')
->join('situations', 'situation.id', '=', 'order_parcels.situation_id')
->select([
'orders.id AS order_id',
'users.id AS user_id',
'order.parcels.id AS parcel_id',
'and so on'
])
->where('some row', '=', 'some row or variable')->get();
I have found this: Get Specific Columns Using “With()” Function in Laravel Eloquent
but nothing from there did not help.
I have users table, columns: id , name , supplier_id. Table suppliers with columns: id, name.
When I call relation from Model or use eager constraints, relation is empty. When I comment(remove) constraint select(['id']) - results are present, but with all users fields.
$query = Supplier::with(['test_staff_id_only' => function ($query) {
//$query->where('id',8); // works only for testing https://laravel.com/docs/6.x/eloquent-relationships#constraining-eager-loads
// option 1
$query->select(['id']); // not working , no results in // "test_staff_id_only": []
// option 2
//$query->raw('select id from users'); // results with all fields from users table
}])->first();
return $query;
In Supplier model:
public function test_staff_id_only(){
return $this->hasMany(User::class,'supplier_id','id')
//option 3 - if enabled, no results in this relation
->select(['id']);// also tried: ->selectRaw('users.id as uid from users') and ->select('users.id')
}
How can I select only id from users?
in you relation remove select(['id'])
public function test_staff_id_only(){
return $this->hasMany(User::class,'supplier_id','id');
}
now in your code:
$query = Supplier::with(['test_staff_id_only:id,supplier_id'])->first();
There's a pretty simple answer actually. Define your relationship as:
public function users(){
return $this->hasMany(User::class, 'supplier_id', 'id');
}
Now, if you call Supplier::with('users')->get(), you'll get a list of all suppliers with their users, which is close, but a bit bloated. To limit the columns returned in the relationship, use the : modifier:
$suppliersWithUserIds = Supplier::with('users:id')->get();
Now, you will have a list of Supplier models, and each $supplier->users value will only contain the ID.
I have same table structure as mentioned in laravel document for HasManyThrough relationship hasManyThrough
countries
id - integer
name - string
users
id - integer
country_id - integer
name - string
posts
id - integer
user_id - integer
title - string
and define a relationship like same as in doc.
public function posts()
{
return $this->hasManyThrough(
'App\Post', 'App\User',
'country_id', 'user_id', 'id'
);
}
Now when I List posts of specific country. I need the information of user of the post too. I mean information from pivot table(users)
$posts = Country::find(2)->posts();
The above returns post data only..
What you need is to eager load the users alongside the posts, can be achieved via the with() method on the Builder:
$posts = Country::find(2)->posts()->with('user')->get();
If you're loading huge amounts of data and don't want the whole User instance loaded, you can even specify which fields to only be retrieved from the users table:
$posts = Country::find(2)->posts()->with('user:id,name')->get();
Then you can simply use $post->user->name or whatever you need when iterating your collection.
Refer to the documentation for more information.
Try this one:
$posts = Country::find(2)->posts()->with('user')->get();
Hello I am learning laravel and I am having an issue retrieving data from my relations.
In my database there are Product and Groups filled with dummy data.
I defined my relationship like this in product model:
public function Group()
{
return $this->hasMany('App\Groups','product_id', 'id');
}
And in my group vice versa with :
public function Product()
{
return $this->belongsTo('App\Product','product_id', 'id');
}
The way I am referencing to my products table is :
$table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
Now I have column product_id in my database under groups, and it is linked to if from products id it seems.
The groups table contains of its auto incremented id and product_id foreign key column.
While products table has auto incremented id and name column.
The issue is here :
How do I return the products that are not null or have value (of products id) in groups table.
I tried something like this in my filter controller:
public function getProductsWithGroup()
{
$Products = Product::with('groups')->get();
return $Products ;
}
But that is giving me call to undefined relations.
I am not sure how to access belongsTo or hasMany methods and whether I need an extra group_id column in my products table.
You named the relationship wrong. It should be groups & define in lowercase as
public function groups()
{
return $this->hasMany('App\Groups','product_id', 'id');
}
And use ->has() to check existence
public function getProductsWithGroup()
{
$Products = Product::has('groups')->get();
return $Products ;
}
->with() is used to eager load and ->has() is used to check existence & filter.
To get the products don't have any groups,
$Products = Product::doesntHave('groups')->get();
To see other ways to use ->has() check, https://laravel.com/docs/5.7/eloquent-relationships#querying-relationship-existence
as stated in the docs the current hasManyThrough can be used when u have something like country > users > posts
which result in something like Country::whereName('xx')->posts;
which is great but what if i have more than that like
country > cities > users > posts
or even
country > cities > towns > users > posts
how would you then implement something like that so you can write the same as above
Country::whereName('xx')->posts; or Town::whereName('xx')->posts;
I created a HasManyThrough relationship with unlimited levels: Repository on GitHub
After the installation, you can use it like this:
class Country extends Model {
use \Staudenmeir\EloquentHasManyDeep\HasRelationships;
public function posts() {
return $this->hasManyDeep(Post::class, [City::class, Town::class, User::class]);
}
}
Here's what I've done. I did some modification to #ctfo's answer, so it will return as collection.
public function posts()
{
$posts = collect();
foreach ($this->towns->get() as $town) {
$post = $town->posts();
if ( $post->count() ) $posts = $posts->merge( $post );
}
return $posts;
}
I hope this can help anyone who came through.
sadly there is no one easy solution, so heres what i found
1- add the other table foreign id into the post table and stick to the hasMany & belongsTo, ex.
posts
id - integer
country_id - foreign
// etc...
title - string
2- go with the hasManyThrough on each table except user & post as there is no need unless you want to go deeper, ex.
countries
id - integer
name - string
cities
id - integer
country_id - foreign
name - string
towns
id - integer
city_id - foreign
name - string
users
id - integer
town_id - foreign
name - string
posts
id - integer
user_id - foreign
title - string
- so lets try with the 2nd option
1- set up your hasMany & belongsTo relations as usual
2- setup the hasManyThrough on the models.
3- to achieve the above example of Country::whereName('xx')->posts we add another method to the country model
// because Country::find($id)->towns, return an array
// so to get all the posts we have to loop over that
// and return a new array with all the country posts
public function posts()
{
$posts = [];
foreach ($this->towns as $town) {
$posts[] = $town->posts;
}
return $posts;
}
4- as the whole thing is working through the foreign_id so we search by the id instead of the name like Country::find($id)->posts()