I have a custom attribute on my User model that's calculates the length of some other tables and returns an integer value:
public function GetCurrentQueueLengthAttribute()
{
// return int
}
I then have an API endpoint that returns a "Team" with all its users (simple Spark pivot)
public function show($teamId)
{
$query = Team::query();
$query->with('users')->where('id', $teamId);
$team = $query->first();
return $team->users->sortBy('currentQueueLength');
return $team;
}
The issue is that the returned data doesn't change order. There are no errors, just the same order of the users every time.
Is there something I'm missing?
The sortBy function is not to be mistaken by the orderBy function, the first one sorts a collection, the second one alters the sql of the query builder.
To be able to use the sortBy function one first needs to retrieve the collection. These functions can still be chained by using:
return $team->users()->sortBy('currentQueueLength');
optionally one could also use orderByRaw if you are willing to write a custom sql query for the sorting.
Related
I got different result from getReward1 and getReward2:
Model:
class User extends Authenticatable
{
public function Products()
{
return $this->hasMany('App\Product', 'user_id');
}
public function getReward1()
{
return $this
->Products
->where('reward', '>', 0)
->where('status', 0)
->sum('reward'); // sum = 7,690,000
}
public function getReward2()
{
return $this
->Products()
->where('reward', '>', 0)
->where('status', 0)
->sum('reward'); // sum = 7,470,000
}
}
getReward1 return 7,690,000 and getReward2 return 7,470,000 (Two different values)
What is difference between $this->Products and $this->Products() ?
$this->products;
// Returns a Collection
$this->products();
// Returns a Relation instance, which is a query builder and can be of type HasMany, BelongsTo...
$this->products()->get();
// Is EXACTLY like doing $this->products for the first time.
The main difference is that products() is just a query that hasn't been executed yet, whereas products are the actual results of this query.
Honestly, even if the name is the same and can be confusing, there are no other similarities between them.
A simple analogy:
DB::table('products')->where('user_id', 18); //could be the $user->products()
DB::table('products')->where('user_id', 18)->get(); //could be $user->products
It's just an analogy, it's not exactly like this internally, but you get the point.
To add more confusion on top of it, Collection methods are ofter similar to those you find in queries; both have where(), first()...
The main thing to remember is that with parentheses, you are still building a query. Until you call get or first, you remain in a query builder.
Without, you already have your results, you are in a Collection (https://laravel.com/docs/8.x/collections).
About the difference you get between getReward1 and getReward2, it's hard to tell exactly what's happening without seeing your database structure.
It can be a lot of things, but when you are calling the sum method, you are calling it on a Collection instance in getReward1 and on a query builder in getReward2 (you are actually executing a query with SELECT SUM(reward)...).
$this->Products() will return an instance of the query builder. The subsequence where clauses will constrain the DB query and then return only the product that you want. These will not be stored in the model instance.
$this->Products will get all of the products from the DB and store them in the model instance as an Eloquent Collection. The subsequent where clauses will then be performed on the Eloquent Collection.
Essentially, the method is doing everything in the DB, whereas, the property is fetching all of the rows and then limiting it with PHP.
The code I'm trying to fix looks like this. I have an Hotel class which is used in a query to get all hotels in an area but it doesn't discard those which are not available. There's a method inside which should be an accessor but it's not written the way I expected it to be:
public function isAvailableInRanges($start_date,$end_date){
$days = max(1,floor((strtotime($end_date) - strtotime($start_date)) / DAY_IN_SECONDS));
if($this->default_state)
{
$notAvailableDates = $this->hotelDateClass::query()->where([
['start_date','>=',$start_date],
['end_date','<=',$end_date],
['active','0']
])->count('id');
if($notAvailableDates) return false;
}else{
$availableDates = $this->hotelDateClass::query()->where([
['start_date','>=',$start_date],
['end_date','<=',$end_date],
['active','=',1]
])->count('id');
if($availableDates <= $days) return false;
}
// Check Order
$bookingInRanges = $this->bookingClass::getAcceptedBookingQuery($this->id,$this->type)->where([
['end_date','>=',$start_date],
['start_date','<=',$end_date],
])->count('id');
if($bookingInRanges){
return false;
}
return true;
}
I wanted to filter out hotels using this query. So this is the query from the controller:
$list = $model_hotel->with(['location','hasWishList','translations','termsByAttributeInListingPage'])->get();
Is it possible to pass the range of days to the function?
By the way the first thing I tried was to use the collection after the query and pass a filter function through the collection and after that paginate manually but although it does filter, but apparently it loses
the "Eloquent" result set collection properties and it ends up as a regular collection, thus it doesn't work for me that way.
Maybe the best approach for that is to create a query scope (source) and put all your logic inside of this function.
after that you can call this scope and pass the dates. Example you will create a query scope and paste your code inside of it.
public function scopeisAvailableInRanges($query, $start_date, $end_date) {
}
then you will invoke this query scope in your controller like this.
$list = $model_hotel::isavailableinranges($start_date, $end_date)->with(['location','hasWishList','translations','termsByAttributeInListingPage'])->get();
keep in mind that inside of your query scope you will return a collection. A collection of all your available hotels.
I have two tables:
main_presentations
so here i have "id" and "isEnabled";
child_presentations
And here i have "id" , "isEnabled" and "idParent";
I want to select in one object this is my code:
public function MainSlider(MainPresentation $MainPresentations, ChildPresentation $ChildPresentations)
{
$MainPresentations = MainPresentation::where('isEnabled', true)->get();
foreach ($MainPresentations as $MainPresentation) {
$AnArray[] = ChildPresentation::where([
['idParent', $MainPresentation['id']],
['isEnabled', true]
])->get();
}
return $AnArray;
}
but this is the result:
enter image description here
What you are doing is executing a query per result, which can be ineffective when it starts getting bigger.
You can:
Use querybuilder
As it follows, you just build a query starting on ChildPresentation, set a relation to MainPresentation table by id and get the collection
public function MainSlider()
{
$childPresentations = ChildPresentation::join('main_presentations','main_presentations.id','child_presentations.idParent')
->where('child_presentations.isEnabled', true)->where('main_presentations.isEnabled', true)->get();
return $childPresentations;
}
If you want all the MainPresentations with their respective ChildPresentations, only the enables ones.
You can take advantage of Laravel relationships and eager loading.
https://laravel.com/docs/5.6/eloquent-relationships
First, set the relationships in your MainPresentation model
In MainPresentation.php
public function childPresentation {
return $this->hasMany('App\ChildPresentation', 'idParent', 'id');
}
Your MainSlider function would be:
(Btw, no idea why you're receiving two arguments if you're overriding them but doesn't matter)
public function MainSlider() {
$mainPresentations = MainPresentation::with(['childPresentations' => function ($advancedWith) {
child_presentation.isEnabled is true
$advancedWith->where('isEnabled', true);
}])
->where('isEnabled', true)->get()->toArray();
return $mainPresentations;
}
This will return an array of MainPresentations that contain an array of child_presentations, with all their childs.
This translates to two queries:
Select * from main_presentations where isEnabled = true;
Select * from child_presentations where isEnabled= true and id in (in the first query);
Laravel then does background work to create the structure you desire when you write ->toArray()
Note: If you have a $visible array in your MainPresentation model, be sure to add: 'childPresentation' to it, otherwise the toArray will not agregage the childs to the parent.
Second note: I advise following some standards whenever you're writing code, usually functions are named camelCase and variables are camelCase.
I am aware that I can use count() to query for Eloquent relationships in Laravel, like so:
if(count($question->answers()))
Where answers() is a hasMany relationship:
public function answers()
{
return $this->hasMany('App\Models\Answer', 'question_id');
}
My question is, how do I do this when $question is not an entire collection but one Model instance?
$question = Question::where('id',$key)->first();
How do I query the above question, and only that question, for a potential relationship using count()?
I always am getting a count() of greater than zero, even when the selected question has no associated answers, which means my if block always runs and returns unwarranted null values:
if(count($question->answers()))
{
//returns nulls
}
Since calling $question->answers() is returning a QueryBuilder instance, calling count() on that will most likely always return 1. If you access $question->answers (as a property and not a method), or use the full logic $question->answers()->get(); it should properly return a Collection, which count() will function correctly on:
$question = Question::where('id',$key)->first();
if(count($question->answers) > 0){
// Do something
}
// OR
if(count($question->answers()->get()) > 0){
...
}
As suggested by #maraboc, you could also eager load your $question with answers using a ->with() clause:
$question = Question::with(["answers"])->where('id',$key)->first();
But even in this case, $question->answers() would still be returning a QueryBuilder instance, so access it as a property for count() to function correctly.
As already pointed count($question->answers()) has no meaning because $question->answers() is a Relation instance, you can call dynamic query method on that but if you want to count elements you need a collection, i.e $question->answers.
So you have two choice:
count the collection: count($question->answers)
ask the database to do the count: $question->answers()->count()
Parentheses matters
i have the following block of code in my Resource Controller:
$travel_company_id = Input::get('travel_company_id');
$transport_type = Input::get('transport_type');
$route_type = Input::get('route_type');
$travelRoutes = TravelRoute::where('travel_company_id', $travel_company_id)
->where('transport_type', $transport_type)
->where('route_type', $route_type)
->get();
Now what this does is it gets travelRoutes based on the parameters supplied. What i want is for it to do is perform a search based on the available parameters, that way if $route_type is empty the search will be performed only on travel_company_id and transport type.
Also if all the parameters are empty then it will simply do a get and return all available records.
I know i can do this with lots of if statements but then if i add a new parameter on the frontend i will have to add it to the backend as well, I was wondering if there was a much simpler and shorter way to do this in laravel.
The where method accepts an array of constraints:
$constraints = array_only(Input::all(), [
'travel_company_id',
'transport_type',
'route_type',
]);
$routes = TravelRoute::where($constraints)->get();
Warning: do not use Input::only() instead of array_only(). They're not the same.
Input::only() fills in any missing items with null, which is not what you want here.
This is pretty hacky and if you spend some time developing a solution I'm sure it could be much nicer. This assumes all the fields in the getSearchFields() function match the input names from the form and database.
/**
* Search fields to retrieve and search the database with. Assumed they match the
* column names in the database
*/
private function getSearchFields()
{
return ['travel_company_id', 'transport_type', 'route_type'];
}
public function search()
{
// Get a new query instance from the model
$query = TravelRoute::query();
// Loop through the fields checking if they've been input, if they have add
// them to the query.
foreach($this->getSearchFields() as $field)
{
if (Input::has($field))
{
$query->where($field, Input::get($field));
}
}
// Finally execute the query
$travelRoutes = $query->get();
}