Background:
What I am doing is I have made a page displaying a table with checkboxes for attendees and events. It was working until I tried to check my checkboxes based on a query through a pivot table through a belongs to many relation.
I have looked at some other threads and tried the same approach to check a pivot for existing entry data. I am using the contains() function to see if my attendee and scheduled_program_segment are matched, but for some reason my code gets this error.
Problem:
I get the error Call to member function contains() on a non-object.
Here is the bit of my code I think is relevent
#foreach( Auth::user()->attendee as $attendee )
<td class="col-lg-1">
{{
Form::checkbox(
($program->name . $attendee->first_name),
'1',
$attendee->scheduled_program_segments->contains($attendee->id)
)
}}
I tried changing to $attendee as well. Same error.
Also, when I run
{{$attendee->scheduled_program_segments()->get()}}
I get the following which I am assuming means I have the pivot table and model set up correctly, but it's not working so maybe I am wrong here.
[{"id":"1","created_at":"2014-11-14 15:19:44","updated_at":"2014-11-14 15:19:44","name":"Minecraft","description":"","date":"2014-11-06","cost":"20.00","start_time":"16:30:00","end_time":"17:30:00","location":"Cookstown","scheduled_program_id":"1","program_segment_id":"1","pivot":{"attendee_id":"1","scheduled_program_segment_id":"1"}},{"id":"1","created_at":"2014-11-14 15:19:44","updated_at":"2014-11-14 15:19:44","name":"Minecraft","description":"","date":"2014-11-06","cost":"20.00","start_time":"16:30:00","end_time":"17:30:00","location":"Cookstown","scheduled_program_id":"1","program_segment_id":"1","pivot":{"attendee_id":"1","scheduled_program_segment_id":"1"}}]
$attendee->scheduled_program_segments
is a m-m relation, so obviously it returns null, because Laravel 4+ relations need to be camelCased in order to work as dynamic properties (that is what you're trying to do).
So you can either rename your relation to scheduledProgramSegments() and then call it:
$attendee->scheduledProgramSegments
// or
$attendee->scheduled_program_segments // yes, this will work as well
or change that line as follows (which I'd rather not suggest):
$attendee->scheduled_program_segments()->get()->contains(...)
Related
I am making a multi-vendor ecommerce website using Laravel 7. I am trying to make an Order History page where in a single can user can view only his/her own orders. I am having a problem building the query on my OrderHistoryController. These are the codes on my controller:
$users = User::get();
$orders = Order::find($users);
return view('order-history', compact('orders'));
And I'm trying to loop $orders on my blade file. I have:
#foreach ($orders as $order)
<div>{{ $order->id}}</div>
<div>{{ $order->grand_total}}</div>
#endforeach
I am trying to pass the order id and order grand total to my view. I don't get any error however it shows a different order details from a different customer. How do I do this?
You should use MySQL (or any other database you are using) table relationships and foreign keys.
So, your orders table, should have columns id, user_id, date, and so on. The important thing is user_id column. You want to make that column a foreign key. That basically means that user_id will hold an id value from another table, in this case user. See how to make foreign key columns in laravel migrations here.
Next up is to use Laravel's built in model relationships. You can read more about them here. Basically, in your orders model you want to have a function user which returns $this->belongsTo(App\Models\User::class) and in your user model you want to have a function orders which returns $this->hasMany(App\Models\Order::class) (or whatever the namespace is for both of them).
That way, you can call $user->orders and get a collection of Order models which will contain only the orders of that particular user.
Definitely read the documentation carefully and learn basic concepts of the framework first and how relational databases function!
You can get a lot of this information just by googling it or reading the documentation of Laravel or any other framework you plan on using! Good luck learning :)
I have defined a many-to-many relationship between Student and Seminar models. How can I find out if one particular student is attending one particular seminar? Non-working example of what I want to achieve is illustrated below:
$seminar->students()->contains($student->id);
The following error is shown when using the above code snippet:
BadMethodCallException with message 'Call to undefined method Illuminate\Database\Query\Builder::contain()'
Try instead:
$seminar->students->contains($student->id);
Presuming $student contains an instance of the Student model you can simplify it further and just use:
$seminar->students->contains($student);
When you add parentheses you're using the Laravel query builder, and you never completed the query. To do it in the manner you had originally you would need:
$seminar->students()->get()->contains($student->id);
This method could be useful if you wanted to add constraints when fetching your students.
But generally you can omit the parentheses and a Collection will be returned, allowing you to use methods like contains.
This has the additional benefit of not re-querying the database once the relationship is loaded, so will generally be a far more efficient means of fetching relationships.
If you haven't already loaded the students and want a database efficient method of checking you could instead use:
$seminar->students()->where('students.id', $student->id)->exists();
In your case the exception is you are calling 'contains()' function (which is for Laravel Collection) on 'Query Builder'. It should be
$seminar->students->get()->contains($student->id);
but this is inefficient since this will retrieve all the students of the seminar.
so instead,
$seminar->students()->wherePivot('student_id', $student->id)->exists();
this method will check in the intermediate table of many to many relationship for particular seminar-student pair, and will return whether exists or not.
The accepted answer is wrong. $seminar->students()->exists($student->id) does not check if the relationship exists. It only checks if the student exists. The student could belong to any seminar and it would still return true.
The correct way to check if a relationship exists without fetching records from the database would be:
$seminar->students()->whereId($student->id)->exists()
Check using query
$seminar->students()->whereKey($student->getKey())->exists();
Check after query (angry), can have memory problems if you have multiple attachments
$seminar->students->contains($student->getKey());
// or
$seminar->students()->get()->contains($student->getKey());
I have 2 models
User
Customer
Each user hasMany customers (aka Accounts)
the user model has
public function customer() {
return $this->hasMany('App\Customer', 'id','customer_id');
}
but when i try to output this:
$user->customer->name
i get an error saying:
Undefined property: Illuminate\Database\Eloquent\Collection::$name
When i use this one, i get the entire customers record output in JSON.
$user->customer
So the relationship is working, but obviously i am missing something. I was sure this was the right way to do it. I swear this worked in Laravel4.2 but now that I'm in Laravel 5 it doesn't.
As the error and the below link says, It is returning a collection (hasMany) not a single object, you need to either loop over the collection or do direct access in the collection based on the index.
that is to say... does doing this work?..
$user->customer[0]->name
http://laravel.io/forum/04-10-2014-undefined-property-illuminatedatabaseeloquentcollectionitem
You should loop over customers, if you want display customers in laravel view you can do the following
#foreach
($user->customer as $cust)
{{$cust->name}}
#endforeach
I have two queries, one is lighter on data by using the pivot table as a filter to get data from the main table (student in this case).
$students=\DB::table('student')->join('school_student', 'student.id', '=','school_student.student_id')->get();
This returns a query result from the controller. But will not load into the blade:
$this->layout->content=\View::make('admin.students.index')->with('student', $students);
Whereas this versions returns a similar more data heavy (i.e. outputs all school data each time)
but works in blade.
$students = \Student::with(array('schools' => function($query){$query->where('school_id', '=', 1);}))->get();
Is it simply that DB and view are incompatible?
If so what is the Laravel 4 method to query one table and it's pivot only.
Any help appreciated.
In the blade
#if($student->count())
The first example produces this error:
Call to a member function count() on a non-object
DB::...->get() returns an array, so you can't call ->count() on it (hence "non-object"), but instead you need count($students).
The reason ->count() works when you do the 'more data heavy' method is that you're using Eloquent and it returns Eloquent Collections.
So, basically, you're doing two different things and expecting to treat them the same.
Also, while I'm here I should point out that I think your Eloquent query isn't quite right. First off you're hardcoding the id as 1 (whereas in the DB-style query you don't care about the school ID, and you just use it to join to the pivot table - maybe you used an incomplete query), but also you're using with but you should probably look at has. with eager-loads models, but has is what you want if you just want to check for a condition on a join table.
I am trying to build a form for a Happening. The Happening references a Places table by place_id.
e.g. happening "OktoberFest" has a place_id 123 which corresponds in table Places to München
These are the relationships declared in the models:
For model Place:
public function happenings()
{
return $this->hasMany('Happening');
}
For model Happening:
public function place()
{
return $this->belongsTo('Place');
}
model Happening has a place_id field linking it to Place.
I am also using {{Form::model($happening, array('route' => array('happenings.update', $happening->id)...}} as form opening
Problem 1: how to create a {{Form::text('......')}} that will be properly prefilled with München when editing the happening Oktoberfest ?
Problem 2: I was trying to get that field to work as an ajax autosuggest (i.e. starting to pull suggestions from the Places table as soon as 3 characters have been entered). I have checked a few implementations but they don't seem to mix correctly with Problem 1
To try and solve Problem 1, I have tried the solution here
Laravel 4 Form builder Custom Fields Macro
but I was unable to make it work.
Long question, it's my very first on stack overflow, please be patient :)
If a Happening is linked to Place via the column 'place_id' you have to supply an id to save in your model/table.
There are a couple of ways that I can think of:
make a list of availble Places in a radio of select, the name will be 'place_id', the value the id of the Place en something like title for the value.
instead of displaying radio's or a select a textfield with autocomplete is a great solution if you got a lot of places. I won't go into detail how to implement it but the general idea is to autocomplete the typed in placename and on selection of that place to put the id of that place in a hidden field named 'placed_id'
After saving the form save your model with the posted place_id
(and check that id if it's valid and existing, never trust user input )