Let's say I have three models with this relationsship
USER
hasMany (app/organisation)
ORGANISATION
hasMany (app/order)
ORDER
For one level I could just go
user->organisations()->get()
And get all the organisations tied to the user. But every organisation also have 0..many ORDER entities. So I want to do this:
user->organisations()->orders()->get()
To get a list of all the orders from all the organisations from a certain user. Is that possible this way?
What you can simply do is implement hasManyThrough() relationship on User model.
public function orders()
{
return $this->hasManyThrough(Order::class, organisation::class);
}
then you can query like,
$user->orders()->get();
Related
In my app, you can create lists of roles that are attached to contacts. So you can assign the contact "Bob" the roles of "Gardener" and "Pet Sitter". Then you can create the list "People" and add "Gardener (Bob)" and "Pet Sitter (Bob)" to it.
I have the following tables:
contacts
id
name
roles
id
name
contact_role (pivot)
id
contact_id
role_id
lists
id
name
contact_role_list (pivot)
id
contact_role_id
list_id
Everything was working smoothly until the second pivot table linked to the first pivot table. My pivot tables are (currently) not having any models so I'm not sure if there is a built-in feature to tackle this in Laravel or if I need to think differently.
I currently have this in my List model:
public function list_roles(): BelongsToMany
{
return $this->belongsToMany(XYZ::class, 'contact_role_list', 'list_id', 'contact_role_id');
}
Is this even close? What do I put where it says XYZ::class?
Ok, so the below is doing what I want, but is there an even better way to do it? The key to solving my problem was to create a Model for ContactRole and changing extends Model to extends Pivot.
I placed this in my List Model:
public function list_roles(): BelongsToMany
{
return $this->belongsToMany(ContactRole::class, 'contact_role_list', 'list_id', 'contact_role_id');
}
And this in my ContactRole Model:
public function contact(): BelongsTo
{
return $this->belongsTo(Contact::class);
}
Now I could reach the contact data by using something like this: List::first()->contact_roles->first()->contact
Any way to use with, pivot or similar to tidy this up even more? Thanks!
I like to approach these issues in terms of Models rather than pivots. I think many new Developers in Laravel get over obsessed with what's going on in the Database which is fine, but theres a lot of Magic going on so you can write very simple code that does a lot of Heavy lifting, so that being said if I fully understand your problem
You have a Contacts Model
This model can have many roles
so in your contacts Model you need a role relationship
public function roles()
{
return $this->belongsToMany(Roles::class);
}
next of course you have a role Model (pun intended)
your each role can have many list
public function lists()
{
return $this->hasMany(List::class)
}
then the idea is now that you have roles on contacts and lists on roles you should be able to have many lists through contact
public function lists()
{
return $this->hasManyThrough(List::class, Role::class);
}
I've done similar things before and for your description it seems like that's the approach you might need to take.
I have a user table that holds all my users. My application allows parents and their children via their own email addresses, but I need to be able to say that "child 1, is a related to parent 1 and parent 2" I want to store all this in the same table, it seems like it's a many-many relationship in so much as many users can belong to any number of other users.
How would I represent an internal many-many relationship in eloquent?
I hitting nothing but net with my attempts.
I would think you'd represent this the same way you would any other many-to-many relationship; only difference is that the same User model holds both the default and inverse relationship:
public function parents(){
return $this->belongsToMany(User::class, "users_users", "user_id", "parent_id");
}
public function children(){
return $this->belongsToMany(User::class, "users_users", "parent_id", "user_id");
}
Note: I may have user_id and parent_id backwards, but that can be adjusted easily.
The only catch I can see with this is trying to get children of children recursively, if that's a concern, but otherwise, this should work for a basic many-to-many.
I am currently building my first App with Laravel and have stumbled upon the problem that I dont know how to setup the relationship Many-to-Many between the Models (User and Group).
I've created a board in which I store the relationship between all users and the Group they are in.
My Problem is that I dont know how to acces and set this up in Laravel.
Im not sure whether I have to user hasMany or belongsToMany.
I am trying to find a method to add a User to Group, so that a new entry will be created in the UserGroups table.
My tables:
User
ID
Name
Email
Group
ID
Name
Creator_ID
UserGroup
User_ID
Group_ID
I appreciate any help, thanks!
If you want to create a many-to-many relationship, it should be belongsToMany, not hasMany.
In the Group model:
public function users()
{
return $this->belongsToMany(Group::class);
}
And in the User model:
public function groups()
{
return $this->belongsToMany(User::class);
}
The pivot table should be called group_user.
https://laravel.com/docs/5.4/eloquent-relationships#many-to-many
In the model class, use belongsToMany as demonstrated here: https://laravel.com/docs/5.4/eloquent-relationships#many-to-many
To add a user to a group, use attach(), as demonstrated here:
https://laravel.com/docs/5.4/eloquent-relationships#the-create-method (scroll to many to many relations)
I'm kinda confused how the eloquent relationships works in Laravel 5.4.
I got a school model that has a "hasMany" relationship with my user model:
public function users()
{
return $this->hasMany('App\User');
}
The user is not required to be linked to a school though, so I haven't put the belongsTo (school) function on my user model.
How should I link the user to a school, when I create the user and how can I pull all users in a specific school into a view, for example?
If the user can only belong to one school, the most straightforward approach would be to add a school_id column to the users table. Since it's not required, you can allow for it to be null. This will allow you to run $school->users to retrieve a list of users for a given school.
I would also recommend adding the belongsTo relationship to the User model, so you can do $user->school to retrieve a user's school when applicable. It's okay that it'll be null for some users.
I have an User model. Each user has certain grades and each grade has certain students.
User and Grade models have one-to-many relationship. Grade and Student models have one-to-many relationship too. But, User and Student models don't have any relationship.
Once User is logged in, he should be able to search all students that belongs to the user.
Do I have to create relationship between these two models to?
If I understand the question correctly, a user has multiple students, so what I'd do is create a one-to-many relationship between them like this:
//User.php
public function students()
{
return $this->hasMany(Student::class);
}
//Student.php
public function user()
{
return $this->belongsToOne(User::class);
}
This would allow you to pick up a users students by doing: $students = $user->students Note: I didn't use () here. If you were to execute $students = $user->students() you'd end up with a query builder object.