How to bulk-select only pivot tables using Eloquent? - php

I have two models with many-to-many relationship defined between them: User and Post. I need to access all of the user's posts' pivot table records. How can I achieve this? For example:
$user->posts()->pivot()->get(); // I need to do something like this
The reason why I need this, is to perform a bulk-update in one query on those pivots. Illustration example:
// set 'times_seen' to 100 for all of the pivot records
$user->posts()->pivot()->update(['times_seen' => 100]);

Your question is not really clear, I'm not sure what you really need so please provide more details.
Data from pivot table is available in $pivot attribute of related model, so you can access it with the following:
foreach ($user->posts as $post) {
echo $post->pivot->someFieldFromPivotData;
}
You can find more info on how to work with pivot tables in the docs: https://laravel.com/docs/5.1/eloquent-relationships#many-to-many
The most efficient way to update all related pivot rows is to directly operate on that table:
// to set to fixed value
DB::table('pivot_table_name')->where('user_id', $user->id)->update(['times_seen' => 1]);
// to increment by one
DB::table('pivot_table_name')->where('user_id', $user->id)->increment('times_seen');

The pivot table usually has just two foreign keys used for connection of two models. If you need to get all posts of specified user, you can do this with $user->posts().
I want to bulk-update the pivot records in one sql query. Iterating through each one of them would be inefficient
If understood you correctly, you want to use attach(), detach() and sync() with an array:
$user->roles()->detach([1, 2, 3]);
$user->roles()->attach([1, 2, 3]);
$user->roles()->sync([1, 2, 3]);
https://laravel.com/docs/5.1/eloquent-relationships#inserting-many-to-many-relationships

Related

How To Bulk Update Pivot Table For Same Attributes In Laravel Many To Many

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

searching a column form pivot table

I have 3 models Eg: Model-1, Model-2, Model-3.
Model-2 and Model-3 has many to many relationship,
So i'm keeping one pivot table like Model-2_Model-3.
Model-1 is has one relationship with model-2 and i'm listing all the data from model-1,
I need to search one column from pivot table for listing Model-1.
For Eg:
$data = Model-1::with('Model-2')->get();
I need to search Model-1 Using pivot table (Model-2_Model-3).
I return pivot connection code already. Pivot is working very well.
You can query pivot table with wherePivot()
Model-1::with('Model-2')->wherePivot('field_name', $value)->get();
If the pivot values are not added, you need to add it as withPivot('field_name')
You may like to use contains, as for many to many relationship you will get collection of second model something like $user->roles, so here you can check if $user->roles->contains('field_name'). as well as $user->roles()->wherePivot('role_id', 1)->get()->isEmpty() or $user->roles()->wherePivot('role_id', 1)->get() depending on your requirement.

Laravel: How to add Relationship in Model when my Foreign keys are in array?

I have a table where I need to save the ids in array, you can see the items in
events_who is a foreign keys. Any solution where I can create a Relationship in my Model to get the data from the foreign keys? I tried belongsToMany and it doesn't work. :(
Any suggestions?
Let's assume we are having 2 models: Event and Person
And a Person can participate to multiple Event
Based on the mentioned relationships, you need to create a pivot table called event_person and define two belongsToMany() relationships in both models:
In the Person model, the relationship will look like:
public function events()
{
return $this->belongsToMany(Event::class, 'event_person');
}
Laravel / MySQL (Relational Database) don't really work this way. You should check out Many to Many Relationships in this case.
Example table schema/layout:
users
|id|name|password|
events
|id|title|body|
event_user (pivot table)
|event_id|user_id|
Usually there won't be an array in a column, you should use tables instead. Besides, normally a foreign key would be a table name(singular) following by _id.

Delete/update laravel pivot table entry by id

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();

How to get value from column that is in a N-N relationship table in Laravel

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

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