I have a model Asset with documents() { $this->hasMany(Document::class); } through a table data_asset_document. I extend Asset into multiple models, one of which is Equipment. In my seeder for Equipment, I attempt to create a Document bound to the Equipment record:
$asset = Equipment::create([...]);
$document = Document::create([
'name' => "$type Purchase Order",
'tracking_number' => app('incrementer')->current()
]);
$asset->documents()->save($document);
Eloquent produces this query:
update `data_document` set `equipment_id` = 1, `data_document`.`updated_at` = 2019-09-20 14:39:48 where `id` = 1
This is obviously incorrect, since data_document does not have an equipment_id column (Documents "belong to" several models besides Asset). How do I rewrite Asset::documents so that produces the correct mapping, even in its extensions? Or do I need to save my Document through a means other than Asset::documents?
Since your extended asset model is called Equipment, Laravel expects your foreign key to be called equipment_id. You will need to specify the actual foreign key of asset_id in your relationship.
https://laravel.com/docs/6.x/eloquent-relationships#one-to-many
hasMany
documents() {
$this->hasMany(Document::class, 'asset_id');
}
The problem is, I'm not convinced your relationship is really hasMany since you mention what looks like a pivot table data_asset_document as being involved. Many-to-many relationships, like mentioned in your title, would use the belongsToMany method.
https://laravel.com/docs/6.x/eloquent-relationships#many-to-many
https://laravel.com/docs/6.x/eloquent-relationships#has-many-through
Related
strange question:
I have 3 Models
Order
with id as PK
Orderline
with id as PK and order_id as FK. brand and partnumber are two separatet colums
Article
with combined PK brand and partnumber
**which is on another database **
One Order hasMany Orderlines. Every Orderline hasOneArticle.
i had make a function within order:
public function articles()
{
$foreignKeys = [
'brand_id',
'article_number',
];
$localKeys = [
'brand',
'partnumber',
];
return $this->hasManyThrough('App\Models\Masterdata\Articles','App\Models\Oms\OrderLine',$foreignKeys,$localKeys,'id','id');
}
How can i retrieve all Attributes from articles through Order?
I tried something like this:
$order = Order::find($orderid)->articles();
dd($order);
//did not work
$order = Order::with('orderlines.articles')->where('id','=',$orderid)->get();
Do you have an idea for me?
You can configure more than one database in the database.php config, and specify the $connection name in the Model class.
For the most part, Eloquent doesn't do JOINs, it just does IN statements on the key values from the preceding query, and programmatically marries the results together after the fact. Partly to avoid the mess of keeping table aliases unique, and partly to offer this kind of support- that your relations don't need to live in the same database.
In other words, what you have there should work just fine. If there's a specific error getting thrown back though, please add it to your post.
I have problems to build a relationship with eloquent.
I have two models created, Spielplan and Verein. In model Spielplan I have the fields Team_ID and Spiel_ID. In model Verein I have the field V_ID and Name. Now I need to join this two tables about Team_ID = V_ID.
This is my model
<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Spielplan extends Model
{
protected $table = 'Spielplan';
public function vereinFunction(){
return $this->hasOne('App\Verein', 'V_ID');
}
}
And this is a function in my web route where I want to get Spiel_ID and Name.
Route::get('test', function(){
$spieleT = App\Spielplan::where('Spiel_ID', '=', 30)->get();
foreach($spieleT as $da){
echo $da->Spiel_ID;
echo $da->vereinFunction->Name;
}
});
The first echo works and I get back Spiel_ID but the second echo gives back ErrorException Trying to get property of non-object.
What is wrong with my code?
Try editing this line:
$spieleT = App\Spielplan::with('vereInFunction')->where('Spiel_ID', '=', 30)->get();.
The with() allows you to fetch the association at the time you use get(). After using get(), you're working with a collection, and can't query the database again.
Try specifying the model primary key as a third argument, because if not, Laravel will assume it is named id, which is not the case.
Allow me to suggest you something: I used to name the tables and fields like you do (in the days I use Codeigniter) but since I started using Laravel around three years ago, I follow Laravel convention (which is recommended, but not imposed). I now name the tables in lowercase, (snakecase) plural, table fields also snakecasm lowercase. Models singular, camelcase similar corresponding table, relation function names as related model, being singular if relation is to one, plural if to many, etc. The advantage of this is among other reflected in model relationship declaration, which is a lot simpler and easier to define.
For instance (only as demonstration of stated above),
tables (with relation one to many:
managers (primarykey: id, name, ......)
technicians (primary key: id, foreingkey: manager_id (related table name in singular plus underscore plus id), name, .....)
models:
Manager:
/* relationships */
public function technicians () // see name as related table, plural due to as many relationship)
{
return $this->hasMany(Technician::class); // as naming convention has followed, you don't need to specify any extra parameters;
}
Techician:
/* relationship */
public function manager() // named as related table, singular due to to one relationship
{
$this->belongsToOne(Manager::class); // again, as naming convention has followed, you don't need to specify any extra parameters;
}
Therefore you can do this:
$manager::find(1);
echo $manager->technicians->first()->name,
or
foreach ($manager->technicians as $technician) {
echo $technician->name;
}
as well as:
$technician->manager->name;
Remember, a proper model relationship definition will save a lot of headache along the way, like the one you have
Hope this help in anyway
I'd like your input on this.
I have a Customer_table with a field name. I have another table called Reservation_table with a Customer_name field.
How can I relate them in such a way that I'd see all the bookings by the specific customer?
In Reservation_table you should have a field(foreign key) userid in order ta have a user for each reservation.
You can using primary key - foreign key relationship to relate/join those two tables. Also, instead of having a 'Customer_name' field as your FK referring to 'name' field in 'Customer_table' table, it is better to have an id (unique) generated for each customer; This way you can have an efficient way of uniquely identifying and relating customer across tables; can save space on Database side as well. Hope this helps!
If you want to use eloquent you must first define a relationship.
One reservation belongs to a user. Here is how to define the relationships:
Inside the Reservation model:
public function user()
{
return $this->belongsTo('App/User'); //User model
}
To define the inverse you do the following:
Inside User model:
public function reservations()
{
return $this->hasMany('App/Reservation'); // Reservation Model
}
Now you can do the following in your controller:
$reservations = Auth::user()->reservations;
Now you have all reservations by the currently logged in user.
I am not sure if I got the question right so ask away.
I'm using laravel and eloquent.
Actually I have problems filtering results from a table based on conditions on another table's attributes.
I have 3 tables:
venue
city
here are the relationships:
a city has many locations and a location belongs to a city.
a location belongs to a venue and a venue has one location.
I have a city_id attribute on locations table, which you may figured out from relationships.
The question is simple:
how can I get those venues which belong to a specific city?
the eloquent query I expect looks like this:
$venues=Venue::with('location')->where('location.city_id',$city->getKey());
Of course that's not gonna work, but seems like this is common task and there would be an eloquent command for it.
Thanks!
A couple of options:
$venues = Venue::whereIn('location_id', Location::whereCityId($city->id)->get->lists('id'))
->get();
Or possibly using whereHas:
$venues = Venue::whereHas('location', function($query) use ($city) {
$query->whereCityId($city->id);
})->get();
It is important to remember that each eloquent query returns a collection, and hence you can use "collection methods" on the result. So as said in other answers, you need a Eager Loading which you ask for the attribute you want to sort on from another table based on your relationship and then on the result, which is a collection, you either use "sortBy" or "sortByDesc" methods.
You can look at an example below:
class Post extends Model {
// imagine timpestamp table: id, publish, delete,
// timestampable_id, timestampble_type
public function timestamp()
{
return $this->morphOne(Timestamp::class, 'timestampable');
}
}
and then in the view side of the stuff:
$posts = App\Post::with('timestamp')->get(); // we make Eager Loading
$posts = $posts->sortByDesc('timestamp.publish');
return view('blog.index', compact('posts'));
I'm using CodeIgniter and have three tables and a model for each:
User - table of users
Product - table of products
UserProduct - table showing which users have which products (two foreign key columns, and some other columns such as date)
In my code I want to display a list for a particular user showing which products they have. So I have a method in the UserProduct class that does a select on the UserProduct table matching for the userId, and a join bringing in all the data I need about each product.
This works fine, but I am concerned now that I am moving down a path of tight coupling. For example, say I want to find out the URL of a product image. I have a method in the product model to return this, I don't want a duplicate method in the UserProduct model, and I don't want to create a coupling by having the UserProduct model trying to access methods in other models (which I don't think CodeIgniter likes you to do).
This problem seems likely to occur in any model that accesses a DB table that has foreign keys where that model may need data from the parent table and want to manipulate it.
Is there an elegant solution, or do I need to accept that foreign keys necessarily create couplings in models or the need for similar methods across models?
TIA,
Phil.
My personal standard is to create 1 controller + 1 model always.
for example site.com/users will use model_users.php
or
site.com/products will use model_products.php
to slim your code and re-use methods use methods params for example a model method to be re-used could be:
function getUsers($data){
foreach($data as $key=>$value){
$this->db->where($key,$value);
}
$query = $this->db->get('users');
return $query->result();
}
the more you extend this method the more you can re-use, just another example of extending:
function getUsers($data,$order_by = false){
foreach($data as $key=>$value){
$this->db->where($key,$value);
}
if($order_by){
foreach($order_by as $key=>$value){
$this->db->order_by($key,$value);
}
}
$query = $this->db->get('users');
return $query->result();
}
//then you call results with this in your controller
$results = $this->model->getUsers(
$data = array('id'=>'12','country'=>'USA'),
$order_by = array('username'=>'DESC')
);
so now you got also order_by , and so on, you can add joins, limit,offset,like etc.. all in the same or quite the same way , the more accurated you are the more you can re-use the same methods