is there any way to get the defined relationships in eloquent model. I have a situation where I need to get the model relationships so I can update all other eloquent models that relies on a specific id before delete it
There's no unified method to iterate over all registered relationships of a class. You can, however, access all the currently loaded relationships of a model instance (via the ->relations attribute or the getRelations() method), but that's not what you're up to. I'd suggest you take a look at laravel's documentation on inserting and updating relationships. So far that's the best laravel provides out of the box, the rest is developing approaches.
Try this function:
public function getRelations()
You can use
$model->getRelations()
function to get all relations
Also refer below link for details https://laravel.com/api/5.7/Illuminate/Database/Eloquent/Concerns/HasRelationships.html#method_getRelations
Related
I have a doub about Laravel. The models are used to define the relationships between the models like hasMany, belongsTo, etc. Also the models are used to define the fillable fields. But he models are only for that? Because I already check some examples that it seems that some queries are executed in the models instead of the controller so Im not understanding if the models should also have the querying of the relationships or not. Can you give a help to understand better what is the correct use of models (what should be placed in the models)?
Its same way to execute queries on model or controller. Written queries in model make your controller more clean. We can write mutator, accessor or query scope in eloquent model. Correct me if I'm wrong.
Visit https://laravel.com/api/5.5/Illuminate/Database/Eloquent/Model.html
You can refer this documentation, it's quite helpful if you want to know deep basics and responsibilities about particular part in Laravel.
Models are mostly used to make an outlook of the data i.e what fields are going to be saved in the database and we also use it to associate the relationships with other related data as you already know but we also use it to alter the values that are either going in/out of the data base which you can check in the documentation in link bellow https://laravel.com/docs/5.6/eloquent-mutators
the main purpose is to divide the code between controller and model (were it best fit to be)
I want to store changes to all fields in Eloquent model into database.
I can do it using created and updated events but there is a problem with multiple foreign relations (described as separate tables).
Example:
User
login
Roles -> hasMany
When I update login field it is easy to write old and new value into database, but when I update Roles relation nothing happens.
How can I track all foreign relations (like hasMany, hasManyThrough, ManyToMany)?
Owen-it has a very nice Library called laravel-auditing, which keeps an easy to query list of all changes that are made to a model, and I think it does quite an awesome piece of work. Have used it and it is worth it to try out.
There is no embedded and simple method to do it.
Eloquent doesn't provide any method to implement observers on related models by design. Many proposal in this way have been rejected by Taylor (just one example).
The only thing you can do, is to create your own methods to do it.
You have many possibilities, here are some of them in order of complexity (some of them are "dirty" :-)
add a created and updated observer on each related model
override the save() or create your own saveAndFire() method on your eloquent instances, and from that method retrieve the parent and call its log methods before saving. (this is a little bit "dirty" imho)
encapsulate all your persistence layer and fire events yourself on saving objects (look at the repository pattern, for example)
I'm confused as to what models are and do in Laravel. I've tried to find some explanations but couldn't find any.
Can someone briefly explain what models are, when I would use them, and why I should use them?
More so, what are fillable and guarded attributes? I don't find they're very well explained in the docs.
For example, I have a table in my database, called login_log, that contains all login attempts. Would I create a model for this? Why?
Model is represented by M when you talk about MVC which stands for Model, View and Controller.
In Laravel Model is simply your database table object. This allows you to interact with your database tables as if they are PHP objects or classes.
Fillable property is used to tell laravel to allow mass assignment for the listed fields
while Guard property is the opposite of fillable
Laravel documentation is the best documentation so far.
See this Links to Understand well : Mass Assignment in Eloquent ORM for Laravel 4.2
Suggestions:
If you are newbie in Laravel, as I am Android Application Developer
i've find solution and understood too.
You have to learn documentation before putting question.
As MVC stands for Model View Controller, Model Deals with Database for example controller ask to Model to give me the first names of Students from the student table an d then controller pass it to the view.
I have just started using Laravel. I have not used Laravel Eloquent before. So I am directly using it on graph database using NeoEloquent.
I know I can create relationship using hasMany() and attach() methods. But I want to create relationship only once. Has anybody used NeoEloquent for creating Unique Relationship.
You may use the hasOne()relationship instead of hasMany() which will ensure that only one relationship of the specified type exists for the model.
I am trying to write a generic function that only will fire if a Model has relationships defined but not be specific to that model.
Is there a property of a model that will tell me if that Model has any relationships regardless of what the Model is or the relationships?
You have access to all your relations using:
$model->getRelations();