delete multiple relationships in codeigniter datamapper orm - codeigniter

I have two models:
users and groups
user has many groups
and group has many users
I try to delete all groups of a user like this, which is not working
$user = new User(1);
$user->groups->delete_all();
Is there a solution to delete all multiple relationships for a model ?

if you want to delete data from multiple table and you have a relation like foreign key you can use this following function by just passing table names (array) and your field name..
function deleteMultiple($tables = array(),$condition = array())
{
if($condition)
$this->db->where($condition);
$this->db->delete($tables);
return;
}

Related

Laravel Query Builder vs Laravel Eloquent ORM in many to many relation

Hi i want to get same result in join query builder as we get in many to many eloquent orm..
$users = DB::table('users')->join('role_user','users.id','=','role_user.user_id')
->join('roles','roles.id','=','role_user.role_id')
->get();
if I use this then I got separate array for same user with role.. for example XYZ user has 3 role then it give me 3 array of same user.
but I want to get it like this user has 3 roles like eloquent
you can use laravel relationship in view file for that you need to define relationship in user model
public function userRoles(){
$this->hasMany(UserRole::class);
}
in controller you need to use With that eager load userRole
To get user roles in view file
$user->userRole
// this will return array of user role related to that user

How to save record in database using belongs to many relation in laravel

I have three tables: restaurant_location, cuisine_restaurant_location and cuisines.
There is a list of all cuisines in my cuisines table. I have all the details of the restaurant in my restaurant_location table. A restaurant can have many cuisines so I made a table cuisine_restaurant_location in which there are two columns cuisine_id and restaurant_id. I have created a belongs to many relation in my restaurant_location model.
restaurant_location model
public function cuisines()
{
return $this->belongsToMany(Cuisine::class, 'cuisine_restaurant_location', 'restaurant_id', 'cuisine_id');
}
I have a form in which all the details of the restaurant along with cuisines is supposed to be added. Right now I am adding all the details of the restaurant. Now the question is how can I insert the cuisines in "cuisine_restaurant_location".
Controller
$rest = new restaurant_location;
$rest->name = $request->input('name');
$rest->description = $request->input('desc');
$rest->save();
$cuisine = new cuisine_restaurant_location
$cuisine_lists = $request->input('cuisines');
foreach ($cuisine_lists as $cuisine_list) {
$cuisine->name = $cuisine_list;
}
You can use the sync and attach methods, described in the Many to many section of the eloquent documentation, for that:
$rest->cuisines()->attach([$cuisineIds])
Where cuisineIds is the list of ids of the cuisines you want to relate.
The difference between sync and attach is that sync will remove all id's not present on the array of ids you are passing.
Try sync() method:
$h = [];
if (isset($input["cuisine_id"])) {
$h = $input["cuisine_id"];
}
$restaurant_location->cuisines()->sync($h);

Eloquent relationship with 3 tables

I'm new to Stack Overflow and Laravel.
I try to develop a variable profilesystem in Laravel and I got 3 tables ('User', 'User_Fields', 'Fields').
The structure of the Fields table is following:
The structure of the user_fields table is following:
The User table is the standard table which came with Laravel 5
Now I want to get all fields from user_fields depending on which user is selected or logged in. If the user_field doesn't exists, the model should return null or create a new record for the user_field.
I tried a lot of "solutions" which came with eloquent like (hasManyThrough, belongsToMany) but I don't get the result I wanted.
Is there any solution with relationship methods?
Thanks for your help, and sorry for my bad english :/
You should be using the belongsToMany()->withPivot() to retrieve the intermediate table columns. Your user_fields is your pivot table so on your user model you should have:
class User extends Model
{
public function fields()
{
return $this->belongsToMany(Field::class, 'user_fields')->withPivot('value');
}
}
Then you can access your values for a user by:
$user = User::find($id);
foreach($user->fields as $field) {
$field->pivot->value;
}

Eloquent - Two Relationships In One?

I've been getting along slowly but surely with Laravel / Eloquent, but am now stumped:
entries Table:
id
user_id
group_id
content
users Table
id
faculty_id
name
group Table:
id
name
faculty Table
id
name
So entries are related to users and groups, and users are related to faculties - I've set up the basic relationships without a problem, and this enables me to find all entries by users from a certain faculty:
Faculty Model:
public function entries()
{
return $this->hasManyThrough('Entry','User');
}
Controller:
Faculty::find(Faculty-ID-here)->entries;
However, I now need to find entries by users that are from a certain faculty AND from a certain group, and I don't know how to write this combination this in Eloquent.
Hope that makes sense! Any suggestions?
Something like:
Entries::whereHas('user', function($q) {
$q->where('faculty_id', $facultyID);
})
->where('group_id', $groupID)
->get();
Assuming you have set up your 'user' relationship.

Laravel save / update many to many relationship

Can anyone help me on how to save many to many relationship? I have tasks, user can have many tasks and task can have many users (many to many), What I want to achieve is that in update form admin can assign multiple users to specific task. This is done through html multiple select input
name="taskParticipants[]"
The catch here is that through the same form (input) you can add/remove users, that's why I have to use sync().
Maybe I should start from the beginning but don't know where to start...
This is my User model:
public function tasks()
{
return $this->belongsToMany('Task','user_tasks');
}
Task model
public function taskParticipants()
{
return $this->belongsToMany('User','user_tasks');
}
TaskController
public function update($task_id)
{
if (Input::has('taskParticipants'))
{
foreach(Input::get('taskParticipants') as $worker)
{
$task2 = $task->taskParticipants->toArray();
$task2 = array_add($task2,$task_id,$worker);
$task->taskParticipants()->sync(array($task2));
}
}
}
This is structure of tables
tasks
id|title|deadline
user_tasks
id|task_id|user_id
tldr; Use sync with 2nd param false
Many-to-many relationship is belongsToMany on both models:
// Task model
public function users()
{
return $this->belongsToMany('User', 'user_tasks'); // assuming user_id and task_id as fk
}
// User model
public function tasks()
{
return $this->belongsToMany('Task', 'user_tasks');
}
In order to add new relation use attach or sync.
Difference between the two is:
1 attach will add new row on the pivot table without checking if it's already there. It's good when you have additional data linked to that relation, for example:
User and Exam linked with pivot table attempts: id, user_id, exam_id, score
I suppose this is not what you need in your situation:
$user->tasks()->getRelatedIds(); // [1,2,3,4,5,6]
$user->tasks()->attach([5,6,7]);
// then
$user->tasks()->getRelatedIds(); // [1,2,3,4,5,6,5,6,7]
2 sync on the other hand, will either remove all relations and set them up anew:
$user->tasks()->getRelatedIds(); // [1,2,3,4,5,6]
$user->tasks()->sync([1,2,3]);
// then
$user->tasks()->getRelatedIds(); // [1,2,3]
or it will setup new relations without detaching previous AND without adding duplicates:
$user->tasks()->sync([5,6,7,8], false); // 2nd param = detach
// then
$user->tasks()->getRelatedIds(); // [1,2,3,4,5,6,7,8]
Here's my notes on how to save and update on all the Eloquent relationships.
in One to One:
You have to use HasOne on the first model and BelongsTo on the second model
to add record on the first model (HasOne) use the save function
example:    $post->comments()->save($comment);
to add record on the second model (BelongsTo) use the associate function
example:    $user->account()->associate($account);    $user->save();
in One to Many:
You have to use HasMany on the first model and BelongsTo on the second model
to add record on the first table (HasMany) use the save or saveMany functions
example:    $post->comments()->saveMany($comments);
to add record on the second model (BelongsTo) use the associate function
example:    $user->account()->associate($account);    $user->save();
in Many to Many:
You have to use BelongsToMany on the first model and BelongsToMany on the second model
to add records on the pivot table use attach or sync functions
both functions accepts single ID or array of ID’s 
the difference is attach checks if the record already exist on the pivot table while sync don’t
example: $user->roles()->attach($roleId);
in Polymorphic One to Many:
You have to use MorphMany on the main model and MorphTo on all the (***able) models
to add records on all the other models use the save
example:    $course->tags()->save($tag);
the pivot table should have the following columns:
. main model ID
. (***able) ID
. (***able) Type
in Polymorphic Many to Many:
You have to use MorphByMany on the main model and MorphToMany on all the (***able) models
to add records on all the other models use the save or saveMany
example:    $course->tags()->save($tag);
example:    $course->tags()->saveMany([$tag_1, $tag_2, $tag_3]);
the pivot table should have the following columns:
. main model ID
. (***able) ID
. (***able) Type
in Has Many Through (shortcut):
You have to use HasManyThrough on the first table and have the normal relations on the other 2 tables
this doesn’t work for ManyToMany relationships (where there’s a pivot table)
however there’s a nice and easy solution just for that.
Here's an article I wrote, inspired by this answer. Important to check it: https://hackernoon.com/eloquent-relationships-cheat-sheet-5155498c209
syncWithoutDetaching([$id_one, $id_two, $id_three]); is what you are looking for. Actually it does the exact thing [sync with 2nd param false] does!
Solved: Use the updateOrInsert(array $attributes, array $values = [])
DB::table('your_pivot_table')->updateOrInsert([
'col' => $someValue
],[
'otherColumn' => $otherVlaue,
]);
}
The sync function obliterates the exiting relationships and makes your array the entire list of relations. You want attach instead to add relations without removing others.
for those who are searching for adding pivot attributes (the middle table attributes), you can use syncWithPivotValues and it also has the second parameter like this
$user->tasks()->syncWithPivotValues($tasksIDs,['day_number' => $day],false);

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