Relationships and querying related models - laravel

I am trying to work out if I have done something correctly. I have a Department Model. A Department can have many DepartmentObjectives. I have also set up the inverse. So this relationship is fine.
I then have a User Model. A User can have many User Objectives, this is set up fine. In my user_objectives table however, there is a link to a department Objective
$table->integer('department_objectives_id')->unsigned()->default(0);
$table->foreign('department_objectives_id')->references('id')->on('department_objectives')->onDelete('cascade');
So a user objective is linked to a department objective. Is this something I need to specify within my models? So should my UserObjectives model have
class UserObjectives extends Model
{
use SoftDeletes;
protected $table = 'user_objectives';
protected $guarded = [];
public function user()
{
return $this->belongsTo('App\User');
}
public function departmentObjectives()
{
return $this->belongsTo('App\DepartmentObjectives');
}
}
For some reason it seems a bit strange doing this. Anyways, when I create a user objective currently, a department objective is selected and I store the id to the department objective. So within my view I can do something like this
{{dd($objective->department_objectives_id)}}
And that will display the id of the department objective it is related too. How can I get the name of the department objective?
Any adivce appreciated
Thanks

Change this
{{dd($objective->department_objectives_id)}}
In your view you can call
{{ $objective->departmentObjectives->name }}
Assuming you have named the name field name.

Related

How get users from section table ? laravel

The idea is that I have relation between two table's section and user
the section_id exist in users table it relation with id section
SO for ex : section_id = 2 > want to bring all users belongs to id section
My code here use id from url and I don't want to do this I want without id bring all users :
public function getAllUsers($id)
{
$data = User::where('section_id',$id)->get();
}
If I'm understanding you correctly, you want to get all the users for a particular Section that have the relationship to that section.
Assuming you have the relationship set up correctly on the Section model:
public function users() {
return $this->hasMany('App\User');
}
I suggest you go about this 'backward' and just pull the users from the Section model itself (eager loading allows one query):
$section = Section::with('users')->first();
$usersForThisSection = $section->users;
If you setup a One to Many relationship you can say things like: $user->section to return the section a user belongs to...and $section->users to get a collection of all the users in a section -- the getAllUsers() is redundant in this case.
Make sure your User and Section models contain these methods. Sounds like your migration was setup properly if you have a section_id column on your users table.
More info on one-to-many here: https://laravel.com/docs/5.8/eloquent-relationships#one-to-many
// app/User.php
class User extends Model
{
public function section() {
return $this->belongsTo('App\Section');
}
}
// app/Section.php
class Section extends Model
{
public function users() {
return $this->hasMany('App\User');
}
}
Test out your relationships in php artisan tinker like so...
$user = User::find(1);
$user->section
$section = Section::find(1);
$section->users
you need a unique identifier to receive section_id's users. receive it from url(get) or ajax(post) . if you worry about users access then use "auth"

Many-to-many withouth relations (Laravel)

I have two application, in two different server.
In the first Laravel application I have my User model, and in the secound application I have my Blog model.
There is a many-to-many relationship between them, a user can have multiple blogs, and one blog can belongs to many user.
They have two different database, but everything is built like its only one app in one server.
They have a REST API, and its communicating between them. The problem is, I cant set up real relations between them (like belongsToMany in the Eloquent Model), and I can't list User's blogs.
Is there a way to copy the "User::blogs()" relation function, with some query work on Blog:: class? For e.g. select all blogs where user_id is equal to 1 in the pivot table?
<?php
class User extends Model{
protected $connection = 'Your Connection';
public function blogs(){
return $this->belongsToMany(Blog::class);
}
}
Blog.php
class Blog extends Model{
protected $connection = 'Your other connection';
public function users(){
return $this->belongsToMany(User::class);
}
}
You can set the multiple connections in your database.php and assign each model a different connection.
I am assuming that you have a user_blogs table. some where
hope this helps.
I found it, like this:
Blog::join('blog_user', 'blogs.id','=','blog_user.blog_id')->where('blog_user.user_id', '=', $this->userId)->get();

laravel use field in Eloquent model from another table

I have a model named "User". I want "Password" field from Eloquent from another table, and when user calls the user::all() method, all selected fields from different tables come in the result.
How can i do that?
Results are not displayed in with() .
my problem solved by using $appends in Eloquent model .
my code :
class User extends Eloquent {
protected $table = 'user';
protected $attributes = ['password'];
protected $appends = ['password'];
public function getPasswordAttribute()
{
return $this->getPAsswordMethod();
}
}
Your question is extremely board and borderline unanswerable but I will give you a board solution.
You are able to establish relationships to other tables via the Model objects you create. Lets pretend you have a Password table which belongs to the User.
User model:
public function password()
{
return $this->hasOne(Password::class, 'FK', 'PK');
}
You can now do User::with('password')->get(['FieldName']); and this will give you all of the passwords which have the above relationship to a user.

working with m:m relationships in eloquent outside laravel

I have been able to set up a m:m relationship in eloquent outside laravel and retrieve records but I have no idea how to add a new record as you dont create the pivot table in the code.
If these are my classes, how would i add a new instance to the M:M relationship between author and publisher?
<?php
include 'eloquent_database.php';
class Publisher extends Illuminate\Database\Eloquent\Model {
public $timestamps = false;
protected $table = 'publisher';
protected $primaryKey = 'publisher_id';
public function authors (){
return $this->belongsToMany('Author', 'author_publisher', 'publisher_id', 'author_id');
}
}
class Book extends Illuminate\Database\Eloquent\Model {
public $timestamps = false;
protected $table = 'book';
protected $primaryKey = 'book_id';
public function author() {
//related table name, pk in current table,
return $this->belongsTo('Author', 'author_id');
}
}
// Create the company model
class Author extends Illuminate\Database\Eloquent\Model {
public $timestamps = false;
protected $table = 'author';
protected $primaryKey = 'author_id';
public function books()
{
//related table, fk IN related table,
return $this->hasMany('Book', 'author_id');
}
public function publishers (){
return $this->belongsToMany('Publisher', 'author_publisher', 'author_id', 'publisher_id');
}
}
I would also need to know how to delete one too. I have seen this documentation http://laravel.com/docs/4.2/eloquent#working-with-pivot-tables but i dont really follow it
Id really appreicate an exxample of how to add and delete a new instance. Also onine there seeems to be so many different versions its hard to find which docs to follow as the code i have works but i didnt get it from the docs - just trial and error
Thanks a lot in advance
edit:
in repsonse to Rays comment i do have a pivot table in the database called author_publisher with author id and publisher id but i have no idea how to work with this pivot table. Do i have to create a class for it? I dont really understand
Here is a reference to said table in the code above
return $this->belongsToMany('Author', 'author_publisher', 'publisher_id', 'author_id');
When having a M:M relationship, make sure you have a table that translates the relationship between author and publisher. An example table could be composed of entries including both author_id and publisher_id. From what you have provided, you lack such a table.
There's another case if you do not have such a table. In order for such a M:M relationship to work, the author table must contain a column called "publisher_id" for simplicity. Likewise the publisher table must contain a column called "author_id". Then in the author model, return $this->hasMany('Publisher', 'author_id') and in the publisher model, return $this->hasMany('Author', 'publisher_id'). You should get the correct answer.

Laravel 4 - Display username based on ID

I have a posts and a users table.
In the posts table, i have a posts_author which is the ID of the user from the users table.
Is there an easy way to display the email address of the user, which is in the users table?
Cheers,
As long as you've set your relationships up it should just be a simple query.
http://laravel.com/docs/eloquent#relationships
Look at the one to many relationships.
(1 User, Multiple posts)
Remember to set the inverse of the relationship up also
If your model has the right relationships then should be as simple as $post->author->email().
You must tweak the author relationship because Eloquent assumes the key will be named author_id.
// Post
public function author() {
return $this->belongsTo('Author', 'posts_author');
}
// Author
public function posts() {
return $this->hasMany('Post');
}
Remember to use eager loading in case you are retrieving emails from more than one post object, or you will end up with n+1 queries.
Providing that you've configured the relationships properly, it should be pretty easy.
Post Model:
class Post extends Eloquent
{
protected $table = 'posts';
public function author()
{
return $this->belongsTo('User', 'posts_author');
}
}
Then User Model:
class User extends Eloquent
{
protected $table = 'users';
public function posts()
{
return $this->hasMany('Post', 'posts_author');
}
}
Then when loading the post you can do the following.
$post = Post::with('author')->find($id);
This will tell Eloquent to join on the users table and load the user data at the same time. Now you can just access all of the user information like this:
$post->author->username;
$post->author->email;
$post->author->id;
// etc etc
Obviously this is just a skeleton, but the assumption is that you have the rest setup.

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