I've got a database structure as follows where item A is in a many to many relationship with B.
This is a true many to many, so:
Item X (object in table A) relates to Y (object in B) multiple times.
Using the laravel attach() function easily adds these records. However, I need to update and delete these items.
The detach() and sync() methods seem to not be appropriate. They assume only one pivot table entry between one record and another record.
If I detach() then ALL items are deleted. That is not what I want.
So the main point of my question:
If I have the id of the pivot table record, how do I delete/update it... given that detach doesn't work as expected.
Or put another way:
How can I interact with a pivot table object directly?
You can use newPivotQuery().
Something like that:
Parent::relation()->newPivotQuery()->where('id', $someId)->delete();
The where() and delete() statements will apply to the pivot query.
Thanks to all,
#devk has pointed out a good solution to the problem if you have the child objects available. I've upvoted this answer because it is true and useful for future reference.
Unfortunately, at this particular point I only have the many-to-many id, so i am answering this with a "No - there is no specific way to access the pivot table by id" using the Pivot or similar objects.
However: to be clear, this can still be done in eloquent using the DB class.
DB::table('many-to-many-lookup')
->where('id', $id)
->take(1)
->delete();
Related
I just found out that when i'm using sync() method for updating pivot table from many to many table, it was executing multiple query.
In my condition, i just trying to update same attributes for all related pivot table records.
This is my script :
foreach ($serials as $serial) {
$newSerials[$serial['id']] = ['warehouse_id' => 1];
}
$record->serials()->sync($newSerials)
Are there any other solution that can do update in pivot table in only one query shot in laravel with Eloquent way ?
I'm pretty sure Query Builder can handle this, but what i need to know in is Eloquent way, that maybe can combine with sync() method, because i alreay implemented sync() to the most of similar case like this in my project.
yes you can, using newPivotQuery() which make the query run directly on pivot table,
you should prepare the array you want to add, give it key value pairs according to your pivot fields names, something like:
foreach ($serials as $serial) {
$newSerials[] =
['serials_id'=>$serial->id,'record_id'=>$record->id,'warehouse_id' => 1];
}
$record->serials()->newPivotQuery()->insert($newSerials);
and there is another way, you can create model for the pivot table by inheriting from pivot, more details in:
https://laravel.com/docs/7.x/eloquent-relationships#defining-custom-intermediate-table-models
i must note that this code insert $newSerials, not updating them, if you want to update the record, method sync() is you best choice
User
uid
Provider
pid
Resolution
rid
ProviderResolution
prid
pid
rid
active
ProviderResolutionUser
prid
uid
class Provider extends Model {
public function resolutions()
{
return $this->belongsToMany('App\Models\Resolution')->withPivot('active')->withTimestamps();
}
}
class Resolution extends Model {
public function providers()
{
return $this->belongsToMany('App\Models\Provider')->withPivot('active')->withTimestamps();
}
}
class User extends Model
{
}
Trying to create a Eloquent relationship with this.
I'm trying to figure out how to fit user into this model. It seems like it's suppose to belongsToMany. Do I need to create a class that represents the pivot?
Then from the case of the User how would I query a list resolutions?
You didn't ask but I personally think it's a lot easier to let the primary key of each table be 'id.' Also, in the case of ProviderResolution, unless you have a specific case for it, you don't need (and shouldn't use) 'prid' at all. Just 'pid', 'rid' and 'active' should be sufficient. The 'pid' and 'rid' make the composite primary key on their own. If you add yet another key ('prid'), then there will be a three-key composite which will technically enable you to have duplicates with your other two primary keys. Yuck. Example: PRID:1, PID:1, RID:1, then PRID:2, PID:1, RID:1. Now you have duplicates but your record is technically still unique because of the PRID key. But, maybe you want it this way for some reason?
For the answer I'm going to assume you are using Laravel 5.4+.
So first off, you don't need a class for the pivot. And secondly, you are currently trying to create a relationship between the user and the existing pivot table between Provider and Resolution by creating a table called 'provider_resolution_user'. If you want to query resolutions for a user, just use the relationship methods which gives you access to the attributes on the pivot table and the related models/tables.
First, setup the 'hasMany' relationships in both classes: Users and Resolutions (Providers already has a relationship to Resolutions, so you can use that relationship if you want to see the related Provider.) Then you'll need a pivot table called 'resolution_user'. Put the 'uid' and the 'rid' in the table. Make the relationships to the corresponding foreign key fields to their parent tables.
Now you can access the relationship directly like:
$user->resolutions->rid (or whatever the attribute is you want)
The previous example assumes you have already created a way to insert records into the pivot table (resolution_user) that relate the user and the resolution together.
If you want to access one of the attributes on the pivot table, 'pivot' creates an object instance with it's own attributes (from the table). You can access it like this:
$user->resolutions->pivot->active;
Of course, these methods are chainable so if you just wanted to see the active resolutions, you could also add a ->where statement.
Hope that helps and wasn't too muddy. I'm happy to clarify any points if need be.
EDITED ANSWER:
Because what you want to do is to disable a row in the provider_resolution table and have that reflect on the correct user, then just create a relationship in both the User model and the Resolution model. So when you disable a row in provider_resolution (pid, rid, active), you can lookup the appropriate user to update by using the inverse relationship between resolution and user. This should give you the user that is assigned to that particular resolution/provider combination. If for some reason you do need to find the user based on a unique combination of the TWO: resolution AND provider, then we might need to talk about polymorphic relationships. Let me know.
I'm working on octoberCMS(laravel framework), I have a doubt on retrieving relation model on where clause.
I have fetched a clothing_type record from "clothing type" model based on its primary key "id".
$clothing_type = ClothingType::where('id',post('clothingtype_id'))->where('status','Active')->first();
This "clothing type" model is related with "products" model, the relation is => each clothing type hasMany products.
Every thing works fine; Now my business logic has two cases, one is to get all the products of the clothing type and another is to get the first product of the clothing type. So I have used the $clothing_type->products to get all the products and $clothing_type->products->first() to get the first product.
Now I have to apply a condition for both the cases. The condition is that only the product whose status is "Active" should be fetched, hence
$products = $clothing_type->products->where('status','Active'); and$first_product_detail = $products->first();.
Every thing works as expected but how come the products are fetched without "get()" method. $clothing_type->products->where('status','Active')->get(); Since I'm new to relation I want to know how this works or is this a bad way to get records or improper assumption. But every thing works good.
$clothing_type = ClothingType::where('id',post('clothingtype_id'))->where('status','Active')->first();
if(count($clothing_type->products))
{
$products = $clothing_type->products->where('status','Active');
$first_product_detail = $products->first();
}
You are doing it the correct way. When you access the relationship as an attribute Eloquent automatically retrieves the records.
However, if you access the relationship as a method, you get the query itself, to which you can add your filters:
if(count($clothing_type->products))
{
$products = $clothing_type->products()->where('status','Active')->get();
$first_product_detail = $products->first();
}
This would solve your problems
(documentation is over here (see the first item))
Edit: Also note that the first method is not a method of Eloquent, but from Collection, which is pretty powerful!
Edit2:
I misread the part of your question where you want to know HOW this is possible. Both Eloquent and Collections have a where method. I assume you understand the working of the Eloquent one, but the one from Collection is pretty much the same (see documentation on the Collection where here)
I prefer the Eloquent one myself, because that limits the amount of records that is retrieved from the database. But if you need all the products (even the inactive ones) later on in your code, just use the Collection method to filter the active ones out
There is nothing to be afraid of...
first() and where()
are functions of both Illuminate\Database\Query\Builder as well as Illuminate\Support\Collection and all first does is limit the records to take 1 and then give you the first record. When you use Builder a query is made to get 1 record and 1 you use it on a collection, all records are first get() and then the first of those records is returned.
Here,
When you do,
$clothing_type->products, Laravel gives you a collection of products...
So...
$products is an object of Illuminate\Support\Collection
and
$products->first() calls for the first() function in that class.
Documentation on where and first methods of a collection...
Im having a problem. I have two tables, places and cuisines, and cuisine_place and in that table I have a column called default (that shows if that cuisine is the default cuisine for that place). But Im having the problem that Im not able to access to that column.
How can I do?
What I want to do is have them in this answer:
$places = Place::all()->with('cuisines')->withPivot('default');
Something like that.
Thanks
You have a many to many relationship between places and cuisines. That relationship would be defined in the following fashion in your models:
public function cuisines(){
return $this->belongsToMany('Cuisine', 'cuisine_place');
}
The above would be a function in your Place class that references its relationship to the cuisines table. By default, Eloquent will pick up the foreign keys in the cuisine_place table (in your case they would probably be called cuisine_id and place_id). If you want to pick up additional columns from that table on calls to the above relationship function, you can use the withPivot function:
public function cuisines(){
return $this->belongsToMany('Cuisine', 'cuisine_place')->withPivot('default');
}
Now, on calls to the cuisines() method in your Place class, you'll receive the default column in the object associated with that table.
Open documentation for Laravel Eloquent Relationships
And read about Retrieving Intermediate Table Columns
You didn't provide your models code so it's difficult to help you with the exact solution
I have a many-to-many relationship where the pivot table has about 20 additional columns. I am using a custom pivot class, and I have successfully set up the code to return an instance of that class when the ->pivot property is accessed on the relation, e.g.
$supplier->products->pivot returns the custom pivot class.
However, when wanting to access the data, I can manually define all the individual attributes of the pivot class (which extends Pivot by the way) in the belongsToMany relationship like this:
return $this->belongsToMany(Product::class, ['prop1', 'prop2', 'prop3'])
...But, how can I retrieve all the pivot data of the class without manually defining them as it ties the relationship declaration very close to the class? Is this possible. If not, it's going to make maintainability a PITA! Ideally, it'd be really nice if withPivot just had a flag to get it all!
In my circumstances, I found it easier to separate all the data into a separate table and model, and add a foreign key in the pivot table to the additional table record. This allows me to use the 'normal' model handling in Laravel and means I don't have to mess around with problems like this!
My use case was a schema of product and supplier with a many-to-many, and each supplier having their own data for the product, namely price, stock, shipping cost / times etc, so I moved all this from the pivot to a SupplierProduct model.
I'll leave this question here, as although this isn't the direct answer to the question (which I fear the answer is 'no'), this is a solution which is viable and can save quite a bit of coding frustration!