So I'm trying to add get a specific data from a related table using the below method, but I don't know if that is the correct way to do it. here is what it looks like.
public function transspecific($lid){
return $this->belongsTo('raplet\Keepertrans')->where("lang_id", $lid);
}
and then I try to get data from it
dd($akeeper->transspecific($akeeper->id));
it doesn't act like there is anything but when I type dd("hello") inside the model, it works. so clearly I have something wrong with my relationship context
What are you are trying to do is adding a [dynamic scope in laravel][1] model, which is totally fine. Except you need to declare the scope seperated from relationship method.
Relationship:
public function keepertrans(){
return $this->belongsTo('raplet\Keepertrans');
}
Scoped:
public function transspecific($lid){
return $this->keepertrans()->where("lang_id", $lid);
}
Then you can call the scope with a get() to execute the query builder:
(SomeOtherRelatedModel::first())->transspecific($someId)->get();
The methods available in Eloquent model for relationship are different than what you need. Whenever you need to add a custom function which internally adds some filters to your query (builder), you need to use scopes
The generic rule of scope function is scope + yourfunction
In your case you will need to create scopeTranspecific function.
Each scope gets the first argument as builder which you update inside the function. The later arguments are optional.
public function scopeTranspecific($query, $lid){
return $query->keepertrans()->where("lang_id", $lid);
}
And then you can use it :
Model::where('column1' , 'value')->transpecific($id)->get()
If you just dump it without ->get() you will get the query builder instance. You will have to do ->get() to get the data
Related
When I try to fetch my user data, I receive the error
Call to a member function first() on null
public function show($id) {
$user=User::findOrFail($id);
$employee = $user->employees->first();
return view('admin.profile')
->with(['employee' => $employee , 'user' => $user]);
}
The problem is probably in your User model.
Check that you have declared the employees relationship:
public function employees()
{
return $this->hasMany(Employee::class); // I'm assuming you have a Employee model with expected column names, but feel free to replace everything with what you actually have in your app
}
If the problem persists, edit your question with your tables structure and your models.
It's very useful to understand the difference between $user->employees and $user->employees().
$user->employees: returns a Collection of employee models, or null if none are found.
$user->employees(): returns a query builder instance that you can chain additional conditions to (where's, etc).
Both options have a first() option available to them, but one is using a Collection method, where the other is using the query builder method.
Some have already suggested this, and I will as well - the safer and simplest solution to your problem is to use the query builder version of the relationship, since there is no risk of the employees() result being null. It also has the added benefit of not needing to load the entire relationship into a collection just to get the first result.
In short: $user->employees()->first(); is the best way to go.
I want to ask about some feature in Laravel, I'm working with some old code written by someone else and I want to understand why it is written this way:
$users = Users::all();
$results = $users->where('age', '>','30')->get();
My question is how can 'where' clause be used with the '$users' variable? This works fine and no error is given and it returns the required results. But as far as i know, 'where' clause can be used like:
Classname::where()->get()
Does the User model implements some feature or use something to be able to call 'where' clause this way? When i try to do the same but with a new model i'm creating I get
"Type error: Too few arguments to function Illuminate\\Support\\Collection::get()
How can 'where' clause be used with the '$users' variable?
The where clause can be used because the all() method returns a Collection, and the where() and get() methods are available on the Collection class.
Does the User model implements some feature or use something to be able to call 'where' clause this way?
Each Eloquent model serves as a query builder which will make you able to add constraints and receive the results with the get() method afterwards.
// Collection::get() is diferent with QueryBuilder::get()
$builder = Users::query(); // you got QueryBuilder object
$builder->where('age', '>','30'); // you got QueryBuilder object
$list = $builder->get(); // you got Collection object
$list->where('age', '>','30'); // you got Collection object
// Collection object has 'get', but it require argument.
// QueryBuilder object has 'get' too, but do not require argument.
I need to override above mentioned methods to skip some database records. Using where is not an option since I would have to use it every single time as there are records in database that I do not need most of the time and I am not allowed to delete them from DB. Here is my attempt of doing this:
class SomeTable extends BaseModel {
public static function first() {
$query = static::query();
$data = $query->first();
if($data && $data->type == 'migration_type') return null;
return $data;
}
public static function get() {
$query = static::query();
$data = $query->get();
foreach($data as $key => $item) {
if($item->type == 'migration_type') unset($data[$key]);
}
return $data;
}
}
The problem with this code is that it works only when direct called on model. If I am using some other functions, like where, before get or first methods, it just skips my overridden method.
What would be the right way to do this and should I put this code within model?
My question is not duplicate as in the answer from mentioned question it is said:
all queries made from Models extending your CustomModel will get this new methods
And I need to override those two functions only for specific model, not for each one in application as not all tables have type column. That's the reason why I have written them within model class.
I need to override above mentioned methods to skip some database records.
Consider a global query scope on the model.
https://laravel.com/docs/5.8/eloquent#global-scopes
Global scopes allow you to add constraints to all queries for a given model. Laravel's own soft delete functionality utilizes global scopes to only pull "non-deleted" models from the database. Writing your own global scopes can provide a convenient, easy way to make sure every query for a given model receives certain constraints.
The issue here is that the where() method on the model returns a QueryBuilder instance where get() will return a Collection instance.
You should be able to override collection's default methods by adding a macro in it's place and can be done like so...
Collection::macro('toUpper', function () {
return $this->map(function ($value) {
return Str::upper($value);
});
});
Extending the query builder instance is not so easy but a good tutorial exists here and involves overriding the application's default connection class, which is not great when it comes to future upgrades.
Because after calling where you're dealing with the database builder and theses methods inside your model aren't being called .. about the issue you might overcome it by using select instead of first directly so will deal with the builder ..
example:
SomeTable::select('col1','col2')->take(1)->get();
another thing overriding these kind of methods is not a good idea if you're working with other developer on the same project.
good luck
I have a user model, and I want to check if a user has been assigned a mentor.
public function mentorapplication()
{
return $this->hasMany(mentorApplication::class, 'user_id');
}
public function mentorAssigned()
{
return ($this->mentorapplication()->status == "counsellorAssigned");
}
when I call $user->mentorAssigned() in tinker I get an undefined property for status.
Any ideas?
A couple of things here. Firstly, your relationship is has-many, which is one-to-many. When you try to use the relationship you should expect a Collection to be returned, rather than a single entity. Therefore trying to access the ->status property on returned collection won't work.
Secondly, when you're trying to access the relationship like this:
$this->mentorapplication()
You will get a HasMany instance, which would allow you to chain on more constraints to the query, just like ->where(...), or ->orderBy(...). You would need to use something like ->get() or ->first() to actually run the query and get the results you're after. You can omit the () here and Laravel will load the relation for you, returning your collection:
$this->mentorapplication
Now, I don't know exactly what it is you're trying to achieve, but say for instance you wanted to see if at least one of the mentorApplication objects assigned to the user has a status of counsellorAssigned, you could do something like this:
public function mentorAssigned()
{
foreach ($this->mentorapplication as $mentorapplication) {
if ($mentorapplication->status == 'counsellorAssigned') {
return true;
}
}
return false;
}
Or you could use Laravel's Collection methods to help you rather than just doing a loop here. There are many approaches you could take so I will just leave it there.
In my controller I have:
$Locations = Locations::where(something);
$Locations->get()->toArray(true);
And inside the model:
function toArray($include_all = false) {
var_dump($include_all);
}
The include all variable is false, although the function gets called.
Is there a reason why it's doing that ?
I want to call a custom toArray because I have more oneToMany relations with different structures that I want to change (some of them are serialized for example)
Thank you
You can use Illuminate\Support\Collection methods such as map() and filter() to modify the collection and at the end of that call toArray() method.
It would be fairly easy to overwrite, however I think there is some confusion that should be cleared up first.
First, the toArray() method you are calling in this case is on the Collection which is the object which is returned when you use get() on your model.
With that said, you can add the following to your Location model to return a custom collection...
public function newCollection(array $models = [])
{
return new CustomCollection($models);
}
Then you write the new CustomCollection class with appropriate namespaces just to make sure it gets auto loaded fine, have it extend \Illuminate\Database\Eloquent\Collection and then you can proceed to override the toArray method.
However, it feels like you randomly selected this toArray() as a proper candidate to perform your logic just because you are already using it. You should think about creating a new function which calls $this->toArray() to grab the results and modify them as you need and return that.
If you need this same functionality on other models, just keep adding that newCollection method where needed.
This is also in the docs as well, might be worth checking out...
https://laravel.com/docs/5.2/eloquent-collections#custom-collections