Laravel detach not working on belongsToMany - laravel

I have this model: Company
Which has a relation: $this->belongsToMany('App\CallList', 'call_list_companies', 'company_id', 'call_list_id')
And vice versa: CallList
Relation: $this->belongsToMany('App\Company', 'call_list_companies', 'call_list_id', 'company_id')
I am able to attach a Company to the CallList
But I cannot detach a Company from a CallList
Why is that?
The code I use for detaching the Company:
$company->call_lists()->detach($call_list);
I also tried the other way:
$call_list->companies()->detach($company);
It just returns null when I do it.
I checked that the both the company and the call list exists and that there was a relation between the two in the database.
Anyone have a clue what I am doing wrong?
I do not get any errors or anything either.
If it's worth mentioning, I am also using a pivot table for the relations.

Filter the relationship query down to just the call list with matching ID and then call detach().
Try:
$company->call_lists()->where('id', $call_list->id)->detach();

I had a similar or the same problem and faced it twice during last 2 years.
I figured out that the relation used soft deletion and it made this problem.
My relation belongsToMany used Pivot class.
use Illuminate\Database\Eloquent\Relations\Pivot;
use Illuminate\Database\Eloquent\SoftDeletes;
class EntityUser extends Pivot
{
use SoftDeletes; // it makes the problem
// some code
}
The table had column deleted_at. But the problem was made SoftDeletes class.
When I run $user->entities()->detach($entity) it returned 1 that means one record was touched or removed, but the table and real results had no changes.
I removed SoftDeletes and it had worked. I also removed that column from the table.
Solution
Remove SoftDeletes from the pivot class. Laravel doesn't have official support of it. https://github.com/laravel/nova-issues/issues/2750
Remove deleted_at from the pivot table. https://laravel.com/docs/9.x/migrations#available-command-aliases

Related

Which relation to use in Laravel?

Which relation to use in Laravel to bind two table through third?
When Doctors can be assigned to some Centers. The intermediate table will be as:
doctor_id | center_id
How to create model in Laravel for this case?
You don't need a model for the intermediate table, simply use attach
Example:
$center = Center::create();
$doctor = Doctor::find(1);
$doctor->centers()->attach($doctor->id);
This is a very simple example but should give you the idea, of how to approach it.
All of it of course requires you have set up your Center and Doctor model with the correct many to many relations
Doctor.php model:
public function centers()
{
return $this->belongsToMany(Doctor::class);
}
See the documentation, for more information.
You could obviously create a model called DoctorsCenter and create it manually by doing this, whenever you want to attach a relation.
DoctorsCenter::create(['center_id' => $center->id, 'doctor_id' => $doctor->id]);
I don't see any good reason for doing this, and would not recommend it.
You can use hasMany or belongsTo relationship of Laravel.
See the laravel documentation, for more information

Laravel - set up a hasMany like relationship without the weak table

I would like your advice in the implementation of the following.
There is an Activity model and a activities table in my project, an activity can have multiple 'tips', and I need to store those tips somewhere.
Each tip has only a text description, if I wasn't using Laravel, I would simply create a table like activity_tips where I would store the id of the activity and the description of the tip, each row been one tip belonging to one activity, maybe an id incremental, but nothing more (at least what I planned).
Now, Laravel comes with this beauty called relationships, but it must be between two models.
I know I can't use something like this because it needs the Tip model (and table).
public function tips(){
return $this->hasMany('App\Tip', 'id_activity', 'id')
->select('id', 'id_activity', 'tip');
}
I could create a Tip model and table, but it doesn't feel right because the Tip table would the 'same' as activity_tips.
Is there any Laravel feature than can help me with that? Also by keeping everything in the model? Maybe use raw sql statements to only have the activity_tips
I found out about the hasMany constrain from laravel and ended up doing a tips table and Tip model.
tips: id, id_activity, tip, created_at, updated_at
public function requirements(){
return $this->hasMany('App\Tips', 'id_activity', 'id');
}
Silly me, I hope someone find this usefull
In the Activity model add:
public function tips(){
return $this->hasMany(Tip::class);
}
This assuming you have a Tip model with 'id', 'activity_id', 'tip'

Laravel Dynamic Eager Loading for Dynamic Relationships

Laravel Version: 5.5
PHP Version: 7+
Database Driver & Version: mysql 5.7+
Scenario:
I have a SaaS application that has flexible database structure, so its fields are bound to change, especially given it has a Json field (for any extra database structure to be created from client side of the application), including relationship based fields. so Account Table can have dynamically created employee_id field, and thus the need to access relationships dynamically
Problem:
I need to EagerLoad models based on this dynamic relationship. If I had something like this:
// Account Model
public function employee(){
return $this->belongsTo(App\Employee);
}
it would be easy. But what I have is this:
public function modelBelongsTo(){
return $this->belongsTo($dynamicClassName, $dynamicForeignKey);
}
Now if I eager load this, I'll get Account Model instance with related Employee on key modelBelongsTo. This is how Eloquent Names based on the function of eagerload. But after this I cannot use this function again to eagerload a second model because it'll just overwrite results on modelBelongsTo key.
Possible Solution Directions:
1) Can I Somehow change laravel's process to use a name I provide?
or
2) Can I write functions on the fly to overcome this so I'll write employee function on the fly?
or
3) Worst Case Scenario: I iterate over all records to rename their keys individually because I am using a pagination, it wouldn't that big of a deal to loop over 10 records.
Us a morph relationship
define the various dynamic classnames say
Employee
Boss
Morph works by having the related key and the table name stored in the parent table, it means to relate them you have to use a join or an orm and you cant have foreign key constraint on it as it links to different tables.
then have your account have morphs where
we have
Account
as top class
then we have
EmployeeAccount, BossAccount
which have their relation to boss and employee
then in Account have morphto relation call it specificAccount()
to which in its child morphs have the morph relation to Account
then add it to $with so to eager load them so when fetching account you could simply do
$account ->specificAccount
to get its morph child. which is nullable
This is totally dynamic such that if you have other classes in future you can just add and add the morph relationship. This may be applied to any reflection or runtime evaluated and loaded classes/code though it is not advisable to do this, as you can always edit code to create new functionality without affecting previous.

Laravel relations with composite, non-standard foreign keys

I unfortunately need to import data from a third-party vendor and use their non-standard database schema with my laravel project. In addition, I need to store multiple "firms," each with their own set of users in my database.
I'm trying to figure out the best way (if it can be done) to use Eloquent to handle the relationships between these tables. So for instance, with my table structure like this:
BmPerson
'id',
'firmId',
'personId'
BmCoverage
'id',
'firmId',
'personId',
'securityId'
BmSecurity
'id',
'firmId',
'securityId'
... for instance, I need to associate a "BmPerson" with many "BmSecurity" through the "BmCoverage" table.
But I need to somehow use composite keys, because I am storing multiple "firms" in each table (per the 3rd party vendor's database schema).
One approach I've used so far is scoping, e.g.: for my BmCoverage model:
public function scopeFromFirm($query,$firmId){
return $query->where('firmId','=',$firmId);//->where('personId','=',$personId);}
public function scopeFromPerson($query,$personId){
return $query->where('personId','=',$personId);//->where('personId','=',$personId);}
Then I can retrieve the coverage list for an individual person, but I still need to somehow be able to associate the "BmCoverage" with the "BmSecurities." I suppose I could just add a scope the BmSecurities class too, but it would be nicer to just use Eloquent.
Has anyone come up with a good way to use composite keys in laravel model relationships, or should I just stick with the scoping method?
There is a package here that seems to be perfect for your case:
Compoships offers the ability to specify relationships based on two
(or more) columns in Laravel 5's Eloquent. The need to match multiple
columns in the definition of an Eloquent relationship often arises
when working with third party or pre existing schema/database.
You would use it like this:
class BmPerson extends Model
{
use \Awobaz\Compoships\Compoships;
public function bmCoverages()
{
return $this->hasMany('App\BmCoverage', ['firmId', 'personId'], ['firmId', 'personId']);
}
}
If every BmSecurity belongs to exactly one BmCoverage, and every BmCoverage belongs to exactly one BmPerson its probably easier to replace 'firmId', 'personId' with bmperson_id in BmCoverage DB; and 'firmId', 'securityId' with bmcoverage_id in BmSecurity. Then you can use default hasMany relations with one key.
Everything you need for this can be found here https://laravel.com/docs/5.2/eloquent-relationships
You can easily define which cols sohuld be the referenced key.
Example:
public function bmCoverages() {
return $this->hasMany('App\BmCoverage', 'firmId', 'id');
}
This would probably belong to your App\Firm or whatever it is called.
In general the hasMany relations looks like this
return $this->hasMany('App\Comment', 'foreign_key', 'local_key');
As you can see you can specify the keys.
As the others have said, you need to use the HasMany and HasManyThrough relationship.
Here from your table definitions, you simply need access to:
Person->BmCoverage(s)
Person->BmSecurity(s) of an individual.
What I think is the major problem here is linking the BmSecurity with BmCoverage as apparently there's no coverage_id per BmSecurity but rather, a composite mapping through firmId and securityId.
In this case, Laravel does not officially support composite keys unfortunately, although you could use a trait like this... but you could also achieve the same with some tricky hasMany.
i.e. on BmCoverage
$this->hasMany('BmSecurity', 'securityId', 'securityId')
->andWhere('firmId', '=', $this->firmId);
Same applies for BmSecurity from BmPerson using HasManyThrough.
Hope that helps.
read laravel hasManyThrough relationship . it will help you to write this query more easily
https://laravel.com/docs/5.1/eloquent-relationships#has-many-through

Laravel5: How are Eloquent model relationships expressed in the database?

There's a missing link I fail to understand.
I use migrations to create database tables and I define the relationships there. meaning.. if I have a person table and a job table and I need a one to many relationship between the person and jobs, I'd have the job table contain a "person_id".
When I seed data or add it in my app, I do all the work of adding the records setting the *_id = values etc.
but somehow I feel Laravel has a better way of doing this.
if I define that one to many relationship with the oneToMany Laravel Eloquent suports:
in my Person model.....
public function jobs()
{
return $this->hasMany('Jobs);
}
what's done on the database level? how do I create the migration for such table? Is Laravel automagically doing the "expected" thing here? like looking for a Jobs table, and having a "person_id" there?
Yep, Laravel is doing what you guess in your last paragraph.
From the Laravel documentation for Eloquent Relationships (with the relevant paragraph in bold):
For example, a User model might have one Phone. We can define this
relation in Eloquent:
class User extends Model {
public function phone()
{
return $this->hasOne('App\Phone');
}
}
The first argument passed to the hasOne method is the name of the
related model. Once the relationship is defined, we may retrieve it
using Eloquent's dynamic properties:
$phone = User::find(1)->phone;
The SQL performed by this statement
will be as follows:
select * from users where id = 1
select * from phones where user_id = 1
Take note that Eloquent assumes the foreign key of the relationship based on the model name. In this case, Phone model is assumed to use a user_id foreign key.
Also note that you don't actually have to explicitly set the foreign key indexes in your database (just having those "foreign key" columns with the same data type as the parent key columns is enough for Laravel to accept the relationship), although you should probably have those indexes for the sake of database integrity.
There is indeed support to create foreign key relationships inside migration blueprints and it's very simple too.
Here is a simple example migration where we define a jobs table that has a user_id column that references the id column on users table.
Schema::create('jobs', function($table)
{
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users');
});
You can also use some other methods that laravel provides such as onDelete() or onUpdate
Of course to understand better the options that are available to you please read the documentation here.
Edit:
Keep in mind that Eloquent is just using fluent SQL wrapper and behind the scenes there are just raw sql queries, nothing magical is happening, fluent just makes your life a lot easier and helpers you write maintainable code.
Take a look here about the Query Builder and how it works and also, as #Martin Charchar stated , here about Eloquent and relationships.

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