Same story as many other questions on this site: I've banged my head into the wall for hours on end trying to figure out these relationships.
I have 3 models where the relationship should work like this:
Model: User
User can belong to many schools.
User belongs to one “Role” separately on each school.
User can be activated/deactivated separately on each school.
Model: School.
School can belong to many users
Model: Role.
Roles would be “Standard” or “Administrator”.
I have a pivot table that connects users and schools.
On the pivot table, I've also experimented with adding 'role_id' and 'is_activated' columns - which I doubt is the correct way about doing this?
I want to access data like this:
User
Get schools belonging to the user.
Get role for current school.
Get activated/deactivated status for current school.
School
Get all users belonging to the school.
Get role for each user.
Get activated/deactived status for each user.
I would've solved this if users could only belong to one school each, but since the same user can belong to several schools it got too complicated for me.
What kind of relationships should I apply on each model?
I would very much appreciate if anyone can point me in the right direction here. Thanks!
You can have a many-to-many relationship between user and school. This would require a pivot table between them to store the ids of the two models. At the end your relationship from a user point of view will end up being:
public function schools() {
return $this->belongsToMany('App\Models\School', 'pivot_table', 'user_id', 'school_id');
}
You can have a look at laravel docs on Many-to-Many
Related
I'm relatively new to PHP and just started to learn Laravel. I leave a few questions regarding a personal learning project I'm working on. Thank you in advance for any feedback!
CONTEXT:
My project is using the default laravel 7.x UI and auth scaffolding. I'v implemented user roles with a roles table and a role_user table. This works as intended (e.g. I can perform CRUD on users and their roles)
Many users can have many roles.
ROLES:
Customer
Agent
Admin
I run into trouble when trying to implement user Statuses. Like this:
Users with the Role of Agent can have only one Status at any given time; either 'AVAILABLE' or 'BUSY'.
QUESTIONS:
#1. How should I define the Agent User/Status relationship? Initially I did Many to Many. I created a statuses table and status_user table. Later I concluded that this was incorrect and changed the relationship to Many to One as seen below. ( I didn't change any of my tables)
In the Users Model:
public function statuses(){
return $this->belongsTo('App\Status');
}
In the Status Model:
public function users(){
return $this->belongsToMany('App\User');
}
Some thoughts:
After having trouble with some queries I'm starting to think using the two tables (statuses and status_user) is in incorrect given how I modeled them above.
Should I rollback and just add a "status_id" column to the user table while keeping the tables as is? I'm starting to think I'm getting the entire relationship wrong.
Maybe I shouldn't be relating status to the users table; instead to a separate 'Agents' table?
Say I have four tables:
users
groups
activities
group_activities
Where a group can have any number of activities and an activity can belong to any number of groups through their intermediate table group_activities, and a user belongs to one group via users.group_id. I want to correctly model a relationship between users and activities so that a user can have any one activity, but only if the group that user belongs to has a relation to that activity.
HasOneThrough doesn't seem to work here, since the group the user is related through has multiple activities. HasManyThrough doesn't work since the user can only have one.
I want to properly model this relationship so that it can be picked up for selection automatically via a Nova relationship field, but I'm struggling to figure out exactly how I would do so. My first thought is a HasOneThrough relation with some set of subqueries, but I can't quite piece together where to start.
How would I do this, or conversely, is it possible via Eloquent's automatic relationship system at all?
To ensure we are on the same idea of your relationships:
The relationship between Groups and Activities is a Many To Many relationship (Many To Many - Larvel Documentation).
The group_activities table is the pivot table.
The relationship between users and groups is a One To Many relationship One To Many - Larvel Documentation and the inverse of it One To Many (Inverse) - Larvel Documentation.
To actually answer your question:
If you want to use a shortcut from users to their activities, the Has Many Through is the correct way. If a group can have arbitrary many activities, and a user belongs to one group, the user will be associated to these arbitrary many activities through the group -hence Has Many Through. Note that this is not really a separate relationship though, it's just a convient shortcut.
If you wan't to associate a user with a single Activity directly, you need to to this via a separate One to Many relationship between Users and Activities.
I'm not entirely sure if I interpret your question correctly, so the following is just an assumption, but do you want to ensure a user can only be associated to an activity thats also associated with the user group? So to restrict possible activites by group? If that is the case, you'd simply need to check if the selected activity is in the activities associated with the users group:
With your relationships set up like this:
class User {
public function activity(){
return $this->belongsTo('App\Activity');
}
public function possibleActivities(){
return $this->hasManyThrough('App\Activity','App\Group');
}
}
you can check and associate activities like this:
if( $user->possibleActivities()->contains( $activity ) ){
$user->activity()->associate($activity);
}
I have users and user_roles tables, and id of user_roles is used as foreign key in users. I fetched data from users using User::with('userRole')->find($user). In returned result userRole is present, however it is empty, instead it was supposed to have data from user_roles for the particular foreign key.
Please, share what can be the possible issues with the functionality or if anyone can explain working of laravel associations in brief.
/* User Model */
public function userRole()
{
return $this->belongsTo('App\UserRole');
}
/* UserRole Model */
public function user()
{
return $this->hasMany('App\User');
}
Thank You,
Many to many relationships in Laravel often require you to have 2 models and 3 tables. One to many relationships require you to have 2 models and 2 tables. One to one relationship also requires you to have 2 models and 2 tables.
Many to many relationship
Let's take User and Role models, since each User can have multiple roles and one Role can be assigned to different users, you will naturally want a Many to many relationship. Now, you will need to create an intermediate table in which you will store the results, why? Because you already defined both User and Role and since it is Many to many none of those objects will have any identifier of the other one inside of them, but rather will have their own identifier in the intermediate table, and this is how Laravel fetches the relationship, it connects Models primary key with foreign key inside of the intermediate table.
One to many relationships
Let's take User and Role models again and let's say that this time, one Role can be assigned to multiple users, but one User can ONLY have 1 Role. Naturally you will have a field role_id inside of your User model and you will connect role_id from users with id from roles.
One to one relationships
Lets take User and Role models again :D Let's say you want to create a separate Role for every user, then you will have 2 models and 2 tables where your users table will have all the users and your roles table will contain id, name, user_id and now when you try to retrieve the relationship, if you define one to one laravel will return only 1 result, no matter if you have multiple same user_id on the roles table, Laravel will return only 1 role because you told him explicitly it's 1-to-1 relationship.
EDIT:
Here is an example of one to one relationship:
/* User Model */
public function userRole()
{
return $this->belongsTo('App\UserRole', 'user_role_id', 'id');
}
#Tim and #Nikola
Thank you, for your efforts mates.
However, I found the reason behind the problem. It was because the wrong naming of userRole function in User model.
I was using foreign key of user_roles as user_roles_id in users table and defined function with name of userRole in User model. This leads to ORM not found the relevant column for attaching user_roles data.
The solution is either I have to change the name of user_roles_id to user_role_id or userRole function name to userRoles. And I choose the first one and it worked fine. :)
For reference on the naming conventions of laravel please refer to Laravel - Database, Table and Column Naming Conventions?.
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 am trying to get my head around some relationships between models in Laravel.
I would like to define the relationship between the following models:
User - the users
Campaign - a campaign
Call - a phone call
Lead - Lead/client
Sale - A sale
Appointment - A scheduled phone call.
This is the way the relationship should be:
A user can be assigned to many campaigns.
A user can have many calls.
One user can have many appointments.
One call belongs to one user.
One call belongs to one campaign.
A campaign can have many calls.
A campaign can have many sales
A lead can be assigned to many campaigns.
A lead can have many sales
One lead belongs to one user in one campaign.
One lead can have many calls
One sale belongs to one campaign
One sale belongs to one user
One appointments belongs to one lead.
I uncertain about how to setup the relationship. Its easy with the one-to-one or many-to-one.
But what about this:
Call->User (one-to-one)
Call->Campaign (one-to-one)
Campaign->Call (one-to-many)
User->Call (one-to-many)
Hopefully I managed to explain it clear enough. Thanks.
I'd recommend reading the Laravel docs on relationships again.
Taking the Call/User relationship as an example, here's what you're looking at:
User --------> Call
(one) (many)
This is clearly a one to many relationship. And if you want to set up both sides of this relationship in terms of an Eloquent model, the relationships are this:
A User hasMany Calls
A Call belongsTo a User
These terms are taken directly from the documentation, in the section entitled One To Many.
So, in code...
User Model
public function Calls()
{
$this->hasMany("Call");
}
(notice that I've made the method name plural - this is my own preference, since using $user->Calls will return a collection if items).
Call Model
public function User()
{
$this->belongsTo("User");
}
Rather than taking the two sides of a relationship in isolation, as you seem to have done in your analysis, consider both sides of the relationship at the same time.