Laravel where define query - php

Question

I'm new in Laravel, I want to know where is the correct place where define functions that query table from DB. In Model or in Controller?
Example:
public function insertUser($firstname, $lastname, $email) {
$user = new User();
$user->firstname = $firstname;
$user->lastname = $lastname;
$user->email = $email;
$user->save();
return $user;
}
The function above where I should declare? Models or Controllers?
Edit:
For example: I need to create a function that return male authors that live in USA and their books. I define AuthorController that use Author (Model). What's the right way to define this function? I write a function in my controller that accept gender and nation as arguments, like:
public function getAuthoursByGenderAndNation($gender, $nation) {
$authors = Author::with("books")->where("gender", "=", $gender)->where("nation", "=", $nation)->get();
return $authors;
}
Or I define a generic function that returns all authors with their books and then apply where clause on function that call this generic function? Like:
public function showAuthors(Request $request) {
$gender = $request->get("gender");
$nation = $request->get("nation");
$authors = $this->getAuthors()->where("gender", "=", $gender)->where("nation", "=", $nation)->get();
return view("authors", ["authors" => $authors]);
}
public function getAuthors() {
$authors = Author::with("books");
return $authors;
}

Answer 1

keep in mind that all application logics should be in controller, and all data operations should be in model. in your question insert user is a application logic, so you should place that on controller, but if you want to define how data is managed, place that method in model. For example, you want a model has ability to retrieve a collection with some condition, may be a user with female gender only so you can Access it via Modell::getFemale()

Answer 2

The function you mention, should be used within a controller. I would recommend that you get a grasp on how MVC works before you dive in Laravel.
Reading that may be useful to you
MVC Concept
Laravel Docs
PHP MVC Tutorial

Answer 3

As according to MCV recommendations.
M (model) should be fat and C (controller) should be thin.
you should write your all database transaction related code in model. Even you can create repositories for database queries.
Your controller should be thin, so you should write only logical code there, like calling model function.
Example:
UserController.php
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Http\Requests\Request;
class UserController extent Controller {
use App\User;
protected $_user;
public function __construct(User $user) {
$this->_user= $user;
}
function saveUser(Request $request) {
$user->fill($request->all());
$user->save();
// or you can directly save by $user->create($request->all());
}
}
This is how you can directly fill data to your User model with $fillable attribute defined there as
$fillable= ['name','email','password'];

Answer 4

If you define your model under the conventions of Eloquent you can simply use the built in Eloquent methods to insert your user as demonstrated in the documentation.
https://laravel.com/docs/5.3/eloquent#inserting-and-updating-models
In the wider scope of your question: 'where to define functions that query the DB table'.
I would suggest typically defining these on the model and looking to make use of the structures provided by Eloquent, for example defining scoped queries on your model.
The code in your controller would then call methods on your model eg.
Model::create();
It also appears you are trying to insert users. I would strongly suggest you look into using Laravel's built in Authentication structures. You'll find these very powerful.
https://laravel.com/docs/5.3/authentication
Hope this helps get you started.