I am new to Eloquent Relationship and all in all in Laravel. I am trying to figure out a way to do many-to many relationship but somehow, I am getting no output. Basically my intention is to clarify the concepts of Eloquent Relationships which is why, I have changed the default table name as well as placed all the models and controllers into separate folders. Although namespacing isn't giving a problem but I believe Eloquent relationships is giving some sort of a problem. Below mentioned is all my code.
Models: namespace App\Relationship_Model;
class roles_model extends Model
{
protected $table="roles_table";
public $timestamps=false;
public function users_table()
{
return $this->belongsToMany(users_model::class);
}
}
class users_model extends Model
{
protected $table="users_table";
public $timestamps=false;
public function roles_table()
{
return $this->belongsToMany(roles_model::class);
}
}
class roles_users_model extends Model
{
public $timestamps=false;
protected $table="roles_users_table";
}
Controller: namespace App\Http\Controllers\Relationship_Controller;
use App\Relationship_Model\roles_model;
use App\Relationship_Model\users_model;
class HomeController extends Controller
{
public function index()
{
$role=users_model::find(1)->roles_model;
dd($role);
}
}
When you do many to many, you don't need a third model like yours : roles_users_model unless you it's an entity which belongs to many users and belongs to many roles.
Laravel uses is own naming convention. It's recommended to follow theses naming.
But in your case you will have to specify with your own parameters :
return $this->belongsToMany('App\Role', 'role_user', 'user_id', 'role_id');
Références :
https://laravel.com/docs/5.6/eloquent-relationships#many-to-many
https://github.com/alexeymezenin/laravel-best-practices#follow-laravel-naming-conventions
Related
I have two models with One-to-Many relationship. I want to display data with relationship in blade.
Products Table
Table name = Products
PrimaryKey = pro_id
ForeignKey = cat_id
Categories Table
Table name = categories
PrimaryKey = cat_id
Products Model Code
namespace App;
use Illuminate\Database\Eloquent\Model;
class productsModel extends Model
{
//code...
protected $table = 'products';
protected $primaryKey = 'pro_id';
// Every Products Belongs To One Category
public function category()
{
# code...
return $this->belongsTo('APP\abcModel','cat_id');
}
}
Categories Model Code
namespace App;
use Illuminate\Database\Eloquent\Model;
class categoryModel extends Model
{
//code...
protected $table = 'categories';
protected $primaryKey = 'cat_id';
// One Category Has Many Products
public function products()
{
# code...
return $this->hasMany('App\productsModel','cat_id','pro_id');
}
}
Controller Code
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\productsModel;
class productsController extends Controller
{
//code...
public function products($category_id='')
{
# code...
$data["products"] = productsModel::where
('cat_id',$category_id)
->get();
$data["categories"] = productsModel::where
('cat_id',$category_id)->first()->category;
echo "<pre>";
print_r($data);
echo "</pre>";
}
}
ERROR:
Symfony\Component\Debug\Exception\FatalThrowableError
Class 'APP\categoryModel' not found
Seems that sometimes you have App, sometimes APP, while PHP is not case sensitive on class names, you might use an operating system (Linux?) that is case sensitive in terms of file names.
I would recommend to have only App everywhere, your error message clearly indicates: APP.
You can clearly see in your model files the namespace is written as "namespace App;"
There you defined the namespace for the app folder. So when you are using this model anywhere, you need to write it as you have defined the namespace. Therefore "App\categoryModel".
Your code should be as follows:
public function category()
{
# code...
return $this->belongsTo('App\categoryModel','cat_id');
}
Also a sincere request, as #alithedeveloper mentioned please follow PSR standards for writing code.
public function category()
{
return $this->belongsTo(abcModel::class,'cat_id');
}
public function products()
{
return $this->hasMany(productsModel::class,'cat_id');
}
This is my Vote model:
namespace App;
use Illuminate\Database\Eloquent\Model;
class Vote extends Model
{
public function user(){
return $this->belongsTo('App\User');
}
public function options(){
return $this->hasMany('App\Option');
}
}
this is my Option model:
namespace App;
use Illuminate\Database\Eloquent\Model;
class Option extends Model
{
public function vote(){
return $this->belongsTo('App\Vote');
}
public function users(){
return $this->belongsToMany('App\User');
}
}
The case is i want to get the users data from many to many relationship in Option model, but started from Vote model. So i get the options data in the Vote model first, then i get the users data in Option model (many to many)
Laravel has no native support for a direct relationship.
I've created a package for cases like this: https://github.com/staudenmeir/eloquent-has-many-deep
class Vote extends Model
{
use \Staudenmeir\EloquentHasManyDeep\HasRelationships;
public function users()
{
return $this->hasManyDeep(User::class, [Option::class, 'option_user']);
}
}
In Laravel 5.6 I'm trying to load data into the user object, so I can view user credentials/settings etc.
Whats annoying is I had it working, but for some reason now It seems to have stopped, and I'm not sure what I've changed to break it.
Anyway I want to load two tables, access and settings. Both of them have user_id field in there with the corresponding user_id in.
In my User.php class I have two functions:
public function access() {
return $this->hasMany(Access::class);
}
public function settings() {
return $this->hasOne(Settings::class);
}
I am not Use-ing them at the top of the class (i.e. use \App\Access) if that makes any difference.
And then the Access class looks like:
namespace App;
use Illuminate\Database\Eloquent\Model;
class Access extends Model
{
protected $table = "access";
}
And the Settings class is very much the same:
namespace App;
use Illuminate\Database\Eloquent\Model;
class Settings extends Model
{
protected $table = "settings";
}
However whenever I try and access Auth::user()->settings or Auth::user()->access I get undefined index: error. It's frustrating because like I said I had it working the other day and I'm not sure what's changed.
Few things you could try here. First, Lazy Eager Load the relationships by loadMissing:
// settings
Auth::user()->loadMissing('settings');
// access
Auth::user()->loadMissing('access');
To load a relationship only when it has not already been loaded, use the loadMissing method
Second, you can use with when querying for a user, although it's not as relevant with using the auth facade:
User::with(['settings', 'access'])->where('atribute', $value)->get();
Last, if you always want the settings and access relationships to always be returned with each user model, set the with attribute on the user model:
public class User {
protected $with = ['settings', 'access'];
...
}
I usually define the inverse relationships on models as well, so Access and Settings would have a BelongsTo relationship defined:
class Access extends Model
{
protected $table = "access";
public function user() {
return $this->belongsTo(User::class);
}
}
class Settings extends Model
{
protected $table = "settings";
public function user() {
return $this->belongsTo(User::class);
}
}
Suppose I got a model with a few relations:
class Author extends Model
{
public function shortStories()
{
return $this->hasMany(ShortStory::class);
}
public function essays()
{
return $this->hasMany(Essay::class);
}
public function books()
{
return $this->hasMany(Book::class);
}
}
Now suppose I got two more models that want to eager load this model with its relations:
class Publisher extends Model
{
public function scopeWithAuthor($query)
{
$query->with('author.shortStories', 'author.essays', 'author.books');
}
}
class Reviewer extends Model
{
public function scopeWithAuthor($query)
{
$query->with('author.shortStories', 'author.essays', 'author.books');
}
}
Problem - if the relations of author change I now need to reflect this in multiple locations.
My question - how do I achieve this in DRY style?
I know that I could add a protected $with to the Author class but then it would always load the relation, not just when required.
With that in mind, one solution I have come up with is to extend the Author model like so:
class AuthorWithRelations extends Author
{
protected $with = ['shortStories', 'essays', 'books'];
}
This then allows me to refactor the scopes of the other models like so:
class Publisher extends Model
{
public function scopeWithAuthor($query)
{
$query->with('authorWithRelations');
}
}
class Reviewer extends Model
{
public function scopeWithAuthor($query)
{
$query->with('authorWithRelations');
}
}
This works well enough but really I was wondering if Laravel provides a better / inbuilt approach to this?
I have this kind of database design
user_classes
- id
- user_id
- class_schedule_id
class_schedules
- id
- class_id
- date
classes
- id
- name
I am now in my UserClass.php Model File
public function classSchedule() {
return $this->belongsTo('\App\ClassSchedule');
}
public static function getClassByUser($user_id){
$user_class = self::where('user_id','=',$user_id)->with('classSchedule');
//other codes here...
}
My question here is that how can I access the name of the class in the class table since the user_classes table doesn't have a direct access to the class instead it should go through first to the class_schedules table.
I am not sure what Eloquent ORM Relationship should I use.
Your help will be greatly appreciated!
thanks! :)
First of all you will need to rename the third class, from class to something else. Then try this,
class user_classes Extends Eloquent {
function classSchedule() {
return $this->hasMany('Class_schedules','class_schedule_id');
}
}
class class_schedules Extends Eloquent {
function userClasses() {
return $this->belongsTo('user_classes', 'class_schedule_id');
}
function classSomething() {
return $this->hasOne('class_something','id');
}
}
class class_something Extends Eloquent {
function classSchedules() {
return $this->belongsTo('class_schedules', 'id');
}
}
Try and follow the naming conventions within Laravel, that will make your life easier down the road.
It uses the snake_cased version of the plural of your model name to define the table name automagically.
Besides that, when you have a relation with single or plural output, name your relation methods accordingly to describe what they do and what kind of output you can expect.
I prefer a dir /app/Models for the models, hence the namespace, you can change this to /app if that's where your models are.
<?php namespace App\Models;
use Illuminate\Database\Eloquent\Model;
class UserClass extends Model
{
// only defined because laravel auto generates alphabetically
protected $table = 'user_classes';
public function user()
{
// given that User model was moved to app/Models, if not, use \App\User
return $this->belongsTo('\App\Models\User');
}
public function classSchedule()
{
return $this->belongsTo('\App\Models\ClassSchedule');
}
}
<?php namespace App\Models;
use Illuminate\Database\Eloquent\Model;
class ClassSchedule extends Model
{
public function class()
{
return $this->belongsTo('\App\Models\Class');
}
}
<?php namespace App\Models;
use Illuminate\Database\Eloquent\Model;
class Class extends Model
{
public function classSchedules()
{
return $this->hasMany('\App\Models\ClassSchedule');
}
}
Now you can basically fetch all entries of UserClass for a particular user, with or without eager loading...
$userClasses = UserClass::where('user_id', $userId)->get();
$userClasses->map(function($userClass) {
echo $userClass->classSchedule->class;
});
More preferably you'll have a method userClasses() with a hasMany relation in your user model