I'm having trouble with eager loading in laravel
I have these models:
class Page extends Eloquent {
public function translations() {
return $this->has_many('Pagestl', 'page_id');
}
}
and
class Pagestl extends Eloquent {
public static $table = 'pages_tl';
public function page() {
return $this->belongs_to('Page', 'id');
}
}
I want a specific page with its translation data of a specific language.
I retrieve the data like this:
$page_data = Page::with(array('translations' => function($query) {
$query->where('lang_id', '=', 'nl')->first();
}))->find($id);
De result is ok-ish. I get all the page data and the translation of 1 language, dutch (nl). But in order to get a field from the language data I have to this:
$page_data->translations[0]->attributes['content_or_whatever'];
..which i find ugly. I feel i should only have to do something like:
$page_data->translations->content;
..but that gives me an error (Trying to get property of non-object).
Am I missing something or is this just the way it is?
I don't find it necessary to do eager-loading here.
Both ways of doing it will result in 2 queries: select the Page with the given id and then find its first translation.
So, I would do:
$page = Page::find($id);
and then
$page_data = Pagestl::where_page_id_and_lang_id($page->id, 'nl')->first();
Then, assuming the content field exists in pages_tl table, we'll get it by doing:
echo $page_data->content;
Finally, your code looks alright; you don't have to have the second parameter when defining the relationships unless they are different from what Laravel expects.
I'll let you find where the problem is with your code (I couldn't figure out from the information given - could be something to do with strings.php)
Related
I'm learning Laravel, so I'm quite new.
I have 2 Models: House and Translation.
My House Model:
use HasFactory;
protected $guarded = ['id'];
public function trans(){
return $this->hasMany(Translation::class);
}
}
My Translation Model:
function House(){
return $this->belongsTo(House::class);
}
}
When I do in the controller something like ($id=2 e.g) :
$house = House::find($id)::with('trans')->get();
I get a result with all houses (there are currently 2 in the DB).
When I just do the query "House::find($id)->get()" it works fine.
What part am I missing?
::with('trans') returns completely new query and forgets everything about your ::find($id)
you need to use load method.
$house = House::find($id);
$house->load('trans');
What happens is, House::find($id) is a method that returns the element by its primary key.
Then, the ::with('trans') gets the result, sees the House class and starts creating a new query builder for the Model.
Finally, the ->get() runs this new query and the end result is what is return for the $house value.
You have two options that will result to what you want to do.
First one is, to find the house entry and then load its relation
$house = House::find($id);
$house->load('trans');
The second option is this:
$house = House::where('id',$id)->with('trans')->first();
The second one is a query builder that results to the first element with id = $id,
and load its relation with translations.
You can check for more details in the laravel documentation. They have a very well-written documentation and the examples help a lot.
I am trying to query data from my database and pass the results to a view called events, the problem I have is that one of my queries will always return the same result because in the where condition the $events_id is the same always. Is there a better way to do the querying? A better logic?
This code is from my controller called EventController:
public function index()
{
$firm_id = DB::table('firms')->where('user_id', auth()->id())->value('id');
$events_id = DB::table('events')->where('firm_id', $firm_id)->value('id');
$events = DB::table('events')->where('firm_id', $firm_id)->get()->toArray();
$actual_events = DB::table('actual_events')->where('event_id', $events_id)->get()->toArray();
return view('events',['events' => $events,'actual_events' => $actual_events]);
}
Since the $events_id is the same every time, the $actual_events will only contain the first result.
The image I have uploaded shows the problem, my table's first three columns are fine. Starting from the fourth they contain repeated values:
As I guess, you need something like this:
$event_ids = DB::table('events')->where('firm_id', $firm_id)->pluck('id');
$actual_events = DB::table('actual_events')->whereIn('event_id', $event_ids)->get()->toArray();
or write about your problem in details and I will try to help you.
you just said that your tables have relation together.
in this case it's better you using the eloquent for that,
first you should type the relations in model of each table like this:
class User extends Authenticatable{
public function cities()
{
return $this->hasmany('App\City'); //you should type your relation
}
}
for relations you can use this link: laravel relationships
after that when you compact the $user variable to your view, you can use this syntax for getting the city value relation to this user: $user->cities;.
I have areas. Each area have N curses
So, each curse belongsTo only one area.
My class
class Area extends Model
{
public function curses()
{
return $this->hasMany('App\Curse');
}
}
My Controller
public function getCursesByAreaId()
{
$areaId = Input::get('areaId'); //ID of selected Area
//area_id is a field of table CURSE. A FK to Area.
$areas = Area::with('curses')->where('area_id', $areaId)->get();
foreach($areas as $area)
{
var_dump($areas);
}
}
Curse Model
class Curseextends Model
{
protected $fillable =
[
'description',
'area_id'
];
}
Using the laravel's debugbar, I see that the query being executed is this:
select * from "areas" where "area_id" = '2'
Isn't it supose to run the relational query ? (with the joins)
Already checked if I'm receiving the right id and it's ok.
the problem is that it's bringing no data at all.
You need something like the following:
$areas = Area::whereHas('curses', function($query) use ($areaId) {
$query->where('area_id', $areaId);
})
->with('curses')
->get();
The whereHas is required only if you want to get the areas that has matching curses.
But, I think you can do it like this way if you only need the related curses because one curse only belong to a single area so, if have the area then you'll get all the curses attached to it:
$area = Area::with('curses')->find($areaId); // Single area
// Access the curses
$curses = $area->curses; // collection of curses
I think you are using relational area_id which is present in curse table, try retrieving the ID of area by id not by area_id, something like this:
$areas = Area::where('id', $areaId)->with('curses')->get();
Hope you get the solution.
Try this :
$areas = Area::whereHas('curses', function($area_query) use ($area_id) {
$area_query->where('area_id', $area_id)
})
->with('curses')
->get();
I already read this piece from the laravel 5.1 documentation:
$users = DB::table('users')
->orderBy('name', 'desc')
->get();
I have no ideia where to write that.
And this is what I tried to write inside my Model:
class Professor extends Model
{
$professor = DB:table('professor')->orderBy('name','asc')->get();
}
Also tried:
class Professor extends Model
{
Professor::orderBy('name')->get();
//$professor = Professor::orderBy('name')->get();
}
Nothing works e.e
All of them give me erros like:
syntax error, unexpected '$professor' (T_VARIABLE), expecting function (T_FUNCTION)
The piece of code your trying to write should not be placed inside a Model. It should be in a controller or a repository if your using a Repository Pattern.
Assuming you got the following in your code.
A table called professors. A model Professor . A Controller called ProfessorsController.
And a route file with the following code get('professors','ProfessorsController#index');
Then on the controller you should have the following code.
class ProfessorsController extends Controller {
public function index()
{
$professors = \DB:table('professors')->orderBy('name','asc')->get();
return view('proffesors')->with('proffessors',$professors);
}
}
This will return an order list of professors to the view. That is if you are using a view to represent the data.
It does not need to be in model. Most of time something like that goes in controller.
In model you need to define relations or functions that would be used application wide on a object.
If you want to do something similar in model you won't use DB::table you need something like:
class Professor extends \Eloquent
{
public function professorsByName(){
$professionCollection = Professor::all()->orderBy('name','asc')->get();
return $professionCollection;
}
}
Please take it as example it's not something that should go in model at least this simple not.
Mental Note
Never use DB::table reason your observer if any won't execute.
I think you all are missing the primary issue with
class Professor extends Model
{
$professor = DB:table('professor')->orderBy('name','asc')->get();
}
This is not how PHP classes work.
OP, you need to brush up on the concepts of OOP.
What you need is something like this:
your controller:
public function myRoutedMethod()
{
$professors = Professor::getModel()->orderBy('name','asc')->get();
foreach($professors as $professor)
{
var_dump($professor->toArray();
}
}
Or probably even better, create a repository to interface with your model and just call $repository->professors()->toArray();
Google search: Laravel Repository
I am trying to get some database information, and I can see the query is being done, but I am unable to come up with content... I have the follows:
class Vendor extends Eloquent {
public function spider()
{
return $this->hasOne('Spider');
}
}
class Spider extends Eloquent {
public function report()
{
return $this->hasMany('Report');
}
}
So... now I am trying to use it as:
$vendor = Vendor::find(1);
$vendor->spider->report->id;
This is not giving me any result - the id is not being fetched. However, I can tell a correct query is being made to the database...
select * from `report` where `report`.`spider_id` = ?
Why is it not giving me anything? I have tried several ways such as... $vendor->spider->first()->report->first()->id... and so on... but all I get is errors.
Thank's.
Report is of type hasMany so a Collection will be retrieved. Process that Collection to find the instance you want.