I have two models
Post.php
id
post
show_id
type = 'movie' or 'tv'
Show.php
id // this only auto increment counter ids
show_id
show_type = 'movie' or 'tv'
the thing is show can be either tv or movie and may two with the same show_id for exmaple one tv could have a show_id of 10 and also one movie can have it but the types are diffrent
i have in post model
public function show(){
return $this->belongsTo('App\Show', 'show_id');
}
in show model
public function post(){
return $this->hasMany('App\Post', 'id');
}
this relationship get the first show with matching show id it sees, wheather its a movie or tv, i want to restrict it to match type column on both sides
post.php:
public function show() {
return $this->belongsTo('App\Show', 'show_id', 'show_id')
->where('type', $this->type);
}
show.php
public function posts() {
return $this->hasMany('App\Post', 'show_id', 'show_id')
->where('type', $this->show_type);
}
UPDATE (the code above does not work!)
Trying to use where clauses (like in the example below) won't work when eager loading the relationship because at the time the relationship is processed $this->f2 is null.
Read more here: Compoships
I just came accross a package https://github.com/topclaudy/compoships
what it does it allows creating relationships based on more than one FK, which laravel doesnt support by default
I think what you're looking for is a polymorphic relation. Instead of having a model that may be one of two "types" there should probably be two separate models on the same relation. For example:
class Post
{
public function Show()
{
return $this->morphTo();
}
}
class TvShow
{
public function Post()
{
return $this->morphMany('App\Post', 'show');
}
}
class Movie
{
public function Post()
{
return $this->morphMany('App\Post', 'show');
}
}
Then your posts table would have a show_id and show_type field that would relate to either a tv show or movie. Check out the docs for more info, I'm not sure of the rest of your project so I'm not 100% this will fit but anytime you start putting "_type" fields in your table you should question whether or not you should be using a polymorphic relation. This will also likely keep your models cleaner and free of a bunch of if statements as you realize there are other differences between movies and shows and how you handle them.
https://laravel.com/docs/5.7/eloquent-relationships#polymorphic-relations
Related
I am trying to update/delete/create in belongsTo relations.
Company has many sports
sports is belonging to Company
Here is two models.
class CompanySports
{
public function company()
{
return $this->belongsTo(Company::class, "company_id","id");
}
class Company
public function sports()
{
return $this->hasMany(CompanySports::class,"company_id","id");
}
}
at controller, when sports is added or modified or remove, what is the best practice to update?
i know that many to many, sync can be used. In this, what is the best solution? Should i compare everytime after loading all from database which is not good practice i believe.
From your code, I would first recommend putting your models in separate files, and ensuring they are singular. If you use the artisan make:model command to generate the stubs, it should do this for you.
// app/CompanySport.php // <-- NOTE singular
class CompanySport // <-- NOTE singular
{
public function company()
{
return $this->belongsTo(Company::class, "company_id","id");
}
}
// app/Company.php
class Company {
public function sports()
{
return $this->hasMany(CompanySport::class,"company_id","id"); // singular
}
}
From there, I find it helpful to build helper methods in the various classes so that the grammar sounds natural and more importantly, belongs to the model. For example:
// app/Company.php
class Company
{
...
public function addSport(CompanySport $sport)
{
$this->sports()->save($sport);
}
public function removeSport(CompanySport $sport)
{
$this->sports()->find($sport->id)->delete();
}
}
These helper functions can then be easily called from anywhere, e.g. controller:
// CompanySportsController.php
public function store(Company $company, CompanySport $sport)
{
$company->addSport($sport);
return redirect('/company/' . $company->id);
}
If you are using these helpers, there is no comparing or sync to be done since you are only using a one to many relationship. Eloquent does everything for you.
Also, I've found this cheatsheet particularly helpful when building out the initial relationships and scaffolding of a new app.
While adding new record of Company Model, you need not to do anything as there is no child for it yet.
While updating an instance of a Company model, again you need not to update anything on its children. As relationship are based on id(primary key) which I believe you don't change while updating.
And now for deleting there are some questions. Do you want to delete the children when the parent is deleting? If so, you can use ON DELETE CASCADE which you can set up in migration like
$table->foreign('company_id')->references('id')->on('companies')->onDelete('cascade');
in your spors table.
Well you can make your own function too like answered in here
Well if you don't want to delete the children, you can use softdelete on your Model. set up the relations then like
CompanySports
public function company()
{
return $this->belongsTo(Company::class, "company_id","id")->withTrashed();
}
This way you can get the parent of a children without any error though the parent is deleted.
I am using laravel 5.7. I have now a situation where i have a Fight model with structure user_id, fightable_id
i have two other tables users and monsters. so users_id refers to users (a user can have many fights) and fightable_id can refer to either a user or a monster (monsters table). so I have to define the functions for the relation ship
for User model i have to do
1.for polymorphic one to many relationship
public function fights()
{
return $this->morphMany('App\Fight', 'fightable');
}
2.for simple one to many relationship
public function fights()
{
return $this->hasMany('App\Fight');
}
I am confused now. ofcourse the only way is to change the functions name. but i will be doing the correct thing by changing the function names right (as both the functions have same name). or is there anything I am doing wrong?
I'm not sure I understand your question completely but I'll try my best!
Also this post will really help you understand the problem you are facing I think,
Laravel morph relationship
Using the code from the post I linked but taking your tables would produce models defined like this.
User Model
class User extends Model
{
public function fights()
{
return $this->hasMany('App\Fight');
}
}
Fight Model
class Fight extends Model
{
public function user()
{
return $this->belongsTo('App\User');
}
public function fightable()
{
return $this->morphTo();
}
}
Monster Model
class Monster extends Model
{
public function fight()
{
return $this->morphOne('App\Fight', 'fightable');
}
}
If you still feel this has not answered your question or need some more help just let me know!
Problem
I have two classes, Users & Posts. A user "hasMany" posts and a post "belongTo" a user. But when I call "User::all()" it doesn't automatically pull the users posts for obvious reasons, because if my user had relations to 100 different tables pulling all users would start to become pretty chunky.
Question
Is there a way to pull all users and all user->posts in one or few lines of code without going through a foreach loop?
I know i can use a mutator but the problem I have is my field is called user_id and i have tested it with this code:
public function getUserIdAttribute($id)
{
return User::find($id);
}
But it will replace "user_id" field value with a user object, Id rather have it set to its own "temporary user" field within the result. I'm trying to find best practice!
Thank you in advance.
What you're looking for is called Eager Loading
Inside your post model :
class Post extends Model
{
protected $table='posts';
public $primaryKey='id';
public function user(){
return $this->belongsTo('App\User','user_id');
}
}
now you want to get post with user use below code :
$posts=Post::with('user')->get();
inside your user model :
class User extends Model
{
public function posts(){
return $this->hasMany('App\Model\Post');
}
}
now you want to get a user with all posts :
$user=User::where('id',$id)->first();
$user_posts=$user->posts;
I have this (simplified) table structure:
users
- id
- type (institutions or agents)
institutions_profile
- id
- user_id
- name
agents_profile
- id
- user_id
- name
And I need to create a profile relationship on the Users model, but the following doesn't work:
class User extends Model
{
public function profile()
{
if ($this->$type === 'agents')
return $this->hasOne('AgentProfile');
else
return $this->hasOne('InstitutionProfile');
}
}
How could I achieve something like that?
Lets take a different approach in solving your problem. First lets setup relationship for the various models respectively.
class User extends Model
{
public function agentProfile()
{
return $this->hasOne(AgentProfile::class);
}
public function institutionProfile()
{
return $this->hasOne(InstitutionProfile::class);
}
public function schoolProfile()
{
return $this->hasOne(SchoolProfile::class);
}
public function academyProfile()
{
return $this->hasOne(AcademyProfile::class);
}
// create scope to select the profile that you want
// you can even pass the type as a second argument to the
// scope if you want
public function scopeProfile($query)
{
return $query
->when($this->type === 'agents',function($q){
return $q->with('agentProfile');
})
->when($this->type === 'school',function($q){
return $q->with('schoolProfile');
})
->when($this->type === 'academy',function($q){
return $q->with('academyProfile');
},function($q){
return $q->with('institutionProfile');
});
}
}
Now you can access your profile like this
User::profile()->first();
This should give you the right profile. Hope it helps.
you can do this by use another method please check this:
a blog Post and Video model could share a polymorphic relation to a
Tag model. Using a many-to-many polymorphic relation allows you to
have a single list of unique tags that are shared across blog posts
and videos. First, let's examine the table structure:
https://laravel.com/docs/5.4/eloquent-relationships#many-to-many-polymorphic-relations
Looks like that should be $this->type rather than $this->$type - since type is a property, not a variable.
I have three tables - "courses", "lessons" and "tasks". Each lesson belongsTo a course, and each task BelongsTo a lesson. I want to output a task, showing the task name, the lesson name, and the course name. How do I access the course table data? To get the lesson information linked to a course, I have used the following in my Task model:
$lessonName = $this->lessons->lesson_name;
To get the course name associated to that lesson, I have tried the following with no success, but I am really guessing here:
$courseName = $this->lessons->courses->course_name;
My model relationships are as follows:
Course.php
public function lessons()
{
return $this->hasMany('App\Lesson');
}
Lesson.php
public function tasks()
{
return $this->belongsTo('App\Task', 'task_id', 'id');
}
Task.php
public function lessons()
{
return $this->belongsTo('App\Lesson', 'lesson_id', 'id');
}
Where am I going wrong? Thanks
there is another way you can do this by using accessors.
on your Task model do the following:
public function getLessonAttribute(){
return Lesson::where('id', $this->attributes[*foreign_key_field*])->first();
}
Here you receive all the data regarding the lesson that the task belongs to, and can use them as any other attribute (field) of the model.
on your Lesson model get the course that it belongs to.
public function getCourseAttribute(){
return Course::where('id', $this->attributes[*course_foreign_key_field*])->first();
}
and then assuming that $task is your collection, you can access the lesson and the course like the following in blade:
$task->lesson->lesson_name and $task->lesson->course->course_name
In your lesson.php model doesn't exist relationship courses so there are your issue. Use answer what is told you #jeroenF
So you want the inverse of hasManyThrough?
The hasManyThrough feature of Laravel (see their site) facilitates connecting your Courses to Task directly, without having the intermediate connection in a separate relationship.
You are looking for the inverse?