I have a films table which contains a many to many relation e.g AgeRatings with a pivot table called film_age_rating which contains a film_id as a foreign key I have this with 3 other relations too.
Right now my app has no functionality to make a deletion request to remove a film, so right now I hard delete rows in the films DB table. When I delete a film from the films table it deletes items, but the data within the pivot table remains unchanged which I don't want to happen.
films_table
public function up()
{
Schema::create('films', function (Blueprint $table) {
$table->uuid('id')->primary();
$table->string('name')->nullable();
}
film_age_rating
public function up()
{
Schema::create('film_age_ratings', function (Blueprint $table) {
$table->bigIncrements('id');
$table->integer('age_rating_id');
$table->uuid('film_id');
$table->timestamps();
});
}
Film Model
public function ageRatings(): BelongsToMany
{
return $this->belongsToMany(
AgeRatings::class,
'film_age_rating',
'film_id',
'age_rating_id'
);
}
Age Rating Model
public function film(): BelongsToMany
{
return $this->belongsToMany(
Film::class,
'film_age_rating',
'age_rating_id',
'film_id'
);
}
I know an option is to add an onDelete cascade to the pivot tables, but that will require lots of migration tables. Is there another way to tackle this without adding a DELETE request for now or is adding the cascade the only option?
Could you please advise me on the most efficient option?
The only way I can imagine is to use softDeletes
On this way, there will be only one query to delete a film, and it will be a logical delete.
You can delete data using the sync() method. It releases the relation from the pivot table. I assuming that you want to delete a film. So this is a sample method in your controller.
public function deleteFilm($id)
{
$film = Film::find($id);
$film->ageRatings()->sync([]);
$film->delete();
}
Related
I need to use a many-to-many relationship to one model. I have an Article model, and I want to make a function so that other articles, typically recommended, can be attached to one article.
This is the function, it should work correctly.
$article = Article::where('id', $request->article_id)->first();
$articles_ids = json_decode($request->articles_ids);
$article->articles()->attach($articles_ids);
I have a question about how to create a table of relations in the database and in the model correctly, I did it like this, but even the migration does not work for me
Model
public function articles()
{
return $this->belongsToMany('App\Models\Article');
}
public function article_recommended()
{
return $this->belongsToMany('App\Models\Article');
}
db
Schema::create('article_article_recommended', function (Blueprint $table) {
$table->unsignedBigInteger('article_recommended_id')->nullable();
$table->foreign('article_recommended_id')
->references('id')->on('article_recommended')->onDelete('set null');
$table->unsignedBigInteger('article_id')->nullable();
$table->foreign('article_id')
->references('id')->on('articles')->onDelete('cascade');
});
error in migration
SQLSTATE[HY000]: General error: 1824 Failed to open the referenced table
'article_recommended' (SQL: alter table `article_article_recommended` add constraint
`article_article_recommended_article_recommended_id_foreign` foreign key
(`article_recommended_id`) references `article_recommended` (`id`) on delete set null)
What are you trying to do should be fairly simple , it's like a following system where each user is related to many users ( same model ) but also same table !
you are here trying to create another table which i consider unnecessary , you only need two tables
articles & recommendations
and the recommendation tabel will act as a pivot table for articles with its self thus creating a many to many relationship with the same table .
Article.php
public function recommendations() {
return $this->belongsToMany(Article::class , 'recommendations' , 'article_id' , 'recommended_article_id');
}
create_recommendations_table.php
Schema::create('recommendations', function (Blueprint $table) {
$table->primary(['article_id','recommended_article_id']);
$table->foreignId('article_id');
$table->foreignId('recommended_article_id');
$table->timestamps();
$table->foreign('article_id')->references('id')->on('article')->onDelete('cascade');
$table->foreign('recommended_article_id')->references('id')->on('articles')->onDelete('cascade');
});
usage
$article->recommendations()->attach($articles_ids);
be sure that the ref-column has exact the same type as the source column (signed, unsigned etc.)
So I am trying to figure a solution to this but not sure exactly how to do this. I have a table that stores all the shows that happen. In a given show I can have multiple providers attend that show. A provider could also attend many shows as well. So how do I store this in the DB and do the eloquent relationship?
Show Schema
Schema::create('shows', function (Blueprint $table) {
$table->increments('id');
$table->string('name');
$table->integer('number')->unsigned();
$table->dateTime('airDate');
$table->string('podcastUrl')->nullable();
$table->timestamps();
});
Provider Schema
Schema::create('providers', function (Blueprint $table) {
$table->increments('id');
$table->string('name');
$table->string('shortName')->nullable();
$table->string('image')->nullable();
$table->string('social')->nullable();
$table->timestamps();
});
Would I store the provider_id in the shows schema?
Update 1
So I created a new migration for a pivot table
Schema::create('provider_show', function (Blueprint $table) {
$table->integer('provider_id')->unsigned()->index();
$table->foreign('provider_id')->references('id')->on('providers')->onDelete('cascade');
$table->integer('show_id')->unsigned()->index();
$table->foreign('show_id')->references('id')->on('shows')->onDelete('cascade');
$table->primary(['provider_id', 'show_id']);
});
Then in the show model I created the following
public function providers()
{
return $this->belongsToMany(Provider::class);
}
Now when I am saving a new show I added a multiselect to select the providers I want
$show = new Show;
$show->name = $request->name;
$show->number = $request->number;
$show->airDate = $request->airDate;
$show->podcastUrl = $request->podcastUrl;
$show->providers()->attach($request->providerList);
$show->save();
Session::flash('message', "Created Successfully!");
return back();
Then when I save I get the following error
SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: provider_show.show_id (SQL: insert into "provider_show" ("provider_id", "show_id") select 1 as "provider_id", as "show_id" union all select 2 as "provider_id", as "show_id")
Create a provider_show migration which will act as your pivot table.
This table would contain both provider_id and show_id which will provide the many-to-many relationship between those entities.
Then on your Provider model you can provide a shows() method which returns a BelongsToMany relationship.
// In your Provider model
public function shows()
{
return $this->belongsToMany('App\Show');
}
Note that Laravel by default looks for a pivot table name based alphabetically on the two relationships.
You can also add the inverse on your Show model by providing a providers() method that also returns a BelongsToMany relationship.
I have 2 models and both they aren't using the ID from the table, but the field internal_id. So i customized my pivot schema but i got stuck on connecting them. Im getting the error:
General error: 1215 Cannot add foreign key constraint (SQL: alter table `seoshop_category_product` add constraint seoshop_category_product_category_id_foreign foreign key
(`category_id`) references `seoshop_categories` (`internal_id`) on delete cascade)
The code for the migration is:
Schema::create('seoshop_category_product', function(Blueprint $table)
{
$table->increments('id');
$table->integer('category_id')->unsigned()->index();
$table->foreign('category_id')->references('internal_id')->on('seoshop_categories')->onDelete('cascade');
$table->integer('product_id')->unsigned()->index();
$table->foreign('product_id')->references('internal_id')->on('seoshop_products')->onDelete('cascade');
$table->timestamps();
});
Both fields as seoshop_products.internal_id as seoshop_categories.internal_id are existing, column types are both int(11).
Can someone tell me what is going wrong?
Migrations for the tables seoshop_categories and seoshop_products
//seoshop_products
public function up()
{
Schema::create('seoshop_products', function(Blueprint $table)
{
$table->increments('id');
$table->integer('shop_id');
$table->integer('internal_id')->signed()->index();
$table->integer('internal_variant_id');
$table->string('visible');
$table->string('tags');
$table->timestamps();
});
}
//Table seoshop_categories
public function up()
{
Schema::create('seoshop_categories', function(Blueprint $table)
{
$table->increments('id');
$table->integer('internal_id')->signed()->index();
$table->datetime('seoshop_created_at');
$table->datetime('seoshop_updated_at');
$table->text('full_description');
$table->timestamps();
});
}
Okay so now i've create my table, and its working as how it should. I need to get my product with categories (many-2-many). So i use
SEOshopProduct::find(1)->with('categories')->get();
After a dd() the categories are empty and i've looked into my query how it is called:
[8] array(3) {
["query"] "select `seoshop_categories`.*, `seoshop_category_product`.`product_id` as `pivot_product_id`, `seoshop_category_product`.`category_id` as `pivot_category_id` from `seoshop_categories` inner join `seoshop_category_product` on `seoshop_categories`.`id` = `seoshop_category_product`.`category_id` where `seoshop_category_product`.`product_id` in (?)"
["bindings"] array(1) {
[0] 8
}
["time"] 0.37
}
The internal_id's of both products and categories is greater then 10.000 and i dont see it back in the query.
My models:
Product:
public function categories(){
return $this->belongsToMany('SEOshopCategory', 'seoshop_category_product', 'product_id', 'category_id');
}
Categories:
public function products(){
return $this->belongsToMany('SEOshopCategory', 'seoshop_category_product', 'category_id', 'product_id');
}
To setup the foreign key constraint, the field definitions need to match exactly. In this case, however, the seoshop_category_product.category_id field is defined as an UNSIGNED INT, but the referenced seoshop_categories.internal_id field is defined as a SIGNED INT. The same is true for the foreign key for your products.
So, you can either update the internal_id fields on your categories and products tables to be unsigned, or you can update your foreign key fields on your pivot table to be signed.
You can tell Laravel what the local and foreign keys are when you define the relationship in your model...
class Product extends Eloquent
{
public function categories() {
return $this->hasMany('Category', 'internal_id', 'id');
}
}
class Category extends Eloquent
{
public function products() {
return $this->hasMany('Product', 'internal_id', 'id');
}
}
I have a table column which holds an array of subject ids selected by the user. There is another table for these subjects and their values. I need to return the values corresponding to the ids saved in the subjects column. To make it more clear suppose that a user have chosen 5 subjects out of 34 subjects and the corresponding ids are saved in the subjects column as a string like this: 2,5,11,21,23
Each of these numbers corresponds to the id of a subject in the subjects table.
//This is the subjects table
public function up()
{
Schema::create('subjects', function (Blueprint $table) {
$table->increments('id');
$table->string('subject', 20);
$table->timestamps();
});
}
//and this is the user_info table
public function up()
{
Schema::create('user_info', function (Blueprint $table) {
...
$table->string('subjects');
...
});
}
How can I return an array of subject values to a view?
// Find whichever user
$user = \App\User::find(1);
// Convert the string of subjects from a string to an array
$subjectIds = explode(',', $user->subjects);
// Load all subjects which match the ids within the subjectIds array
$subjects = \App\Subjects::whereIn($subjectIds)->get();
// Do something with the subjects
foreach($subjects as $subject) {
// Output the subject name
var_dump($subject->name);
}
After some searching around I found that maybe the best solution for my problem was to use the Many to Many relationship. So I removed the subjectscolumn from user_info table. Then I created the pivot table subject_user to save the id of user and their subjects ids in this table.
This is the pivot table schema:
Schema::create('subject_user', function (Blueprint $table) {
$table->increments('id');
$table->integer('user_id')->index();
$table->integer('subject_id')->index();
$table->timestamps();
});
Then in the User and Subject models I established the proper many to many relationship as follows:
//User Model
public function subjects()
{
return $this->belongsToMany('App\Subject')->withTimestamps();
}
//Subject Model
public function users()
{
return $this->belongsToMany('App\User');
}
Finally in the controller i used the attach() and sync() methods to populate or update the pivot table.
//In store method
$user->subjects()->attach($subjects);
//In update method
$user->subjects()->sync($subjects);
The difference between attach and syn is described here.
I have a User model which belongsToMany() Conferences. Conferences hasMany Users, also a m:m relationship.
I am working on a link() method in my ConferencesController, but I'm not sure how to go about.
I collect the given Conference by id, and the Auth::check-ed User. How do I add the conference and user into the pivot table?
create a pivot table
//conference_user
Schema::create('conference_user', function(Blueprint $table) {
$table->increments('id');
$table->integer('conference_id')->unsigned()->index();
$table->foreign('conference_id')->references('id')->on('conferences');
$table->integer('user_id')->unsigned()->index();
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
});
now in User model, add this method
public function conferences()
{
return $this->belongsToMany('Conference','conference_user');
}
and in Conference model, add this method
public function users()
{
return $this->belongsToMany('User','conference_user');
}
now in your controller, you can use something like this
$conferences=$user->conferences;
or
$users=$conference->users;