When I delete a row using this syntax:
$user->delete();
Is there a way to attach a callback of sorts, so that it would e.g. do this automatically:
$this->photo()->delete();
Preferably inside the model-class.
180
votes
14 Answers
248
votes
I believe this is a perfect use-case for Eloquent events (http://laravel.com/docs/eloquent#model-events). You can use the "deleting" event to do the cleanup:
class User extends Eloquent
{
public function photos()
{
return $this->has_many('Photo');
}
// this is a recommended way to declare event handlers
public static function boot() {
parent::boot();
static::deleting(function($user) { // before delete() method call this
$user->photos()->delete();
// do the rest of the cleanup...
});
}
}
You should probably also put the whole thing inside a transaction, to ensure the referential integrity..
221
votes
You can actually set this up in your migrations:
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
Source: http://laravel.com/docs/5.1/migrations#foreign-key-constraints
You may also specify the desired action for the "on delete" and "on update" properties of the constraint:
$table->foreign('user_id') ->references('id')->on('users') ->onDelete('cascade');
57
votes
Note: This answer was written for Laravel 3. Thus might or might not works well in more recent version of Laravel.
You can delete all related photos before actually deleting the user.
<?php
class User extends Eloquent
{
public function photos()
{
return $this->has_many('Photo');
}
public function delete()
{
// delete all related photos
$this->photos()->delete();
// as suggested by Dirk in comment,
// it's an uglier alternative, but faster
// Photo::where("user_id", $this->id)->delete()
// delete the user
return parent::delete();
}
}
Hope it helps.
35
votes
26
votes
There are 3 approaches to solving this:
1. Using Eloquent Events On Model Boot (ref: https://laravel.com/docs/5.7/eloquent#events)
class User extends Eloquent
{
public static function boot() {
parent::boot();
static::deleting(function($user) {
$user->photos()->delete();
});
}
}
2. Using Eloquent Event Observers (ref: https://laravel.com/docs/5.7/eloquent#observers)
In your AppServiceProvider, register the observer like so:
public function boot()
{
User::observe(UserObserver::class);
}
Next, add an Observer class like so:
class UserObserver
{
public function deleting(User $user)
{
$user->photos()->delete();
}
}
3. Using Foreign Key Constraints (ref: https://laravel.com/docs/5.7/migrations#foreign-key-constraints)
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
14
votes
As of Laravel 5.2, the documentation states that these kinds of event handlers should be registered in the AppServiceProvider:
<?php
class AppServiceProvider extends ServiceProvider
{
/**
* Bootstrap any application services.
*
* @return void
*/
public function boot()
{
User::deleting(function ($user) {
$user->photos()->delete();
});
}
I even suppose to move them to separate classes instead of closures for better application structure.
5
votes
It is better if you override the delete method for this. That way, you can incorporate DB transactions within the delete method itself. If you use the event way, you will have to cover your call of delete method with a DB transaction every time you call it.
In your User model.
public function delete()
{
\DB::beginTransaction();
$this
->photo()
->delete()
;
$result = parent::delete();
\DB::commit();
return $result;
}
3
votes
To elaborate on the selected answer, if your relationships also have child relationships that must be deleted, you have to retrieve all child relationship records first, then call the delete() method so their delete events are fired properly as well.
You can do this easily with higher order messages.
class User extends Eloquent
{
/**
* The "booting" method of the model.
*
* @return void
*/
public static function boot() {
parent::boot();
static::deleting(function($user) {
$user->photos()->get()->each->delete();
});
}
}
You can also improve performance by querying only the relationships ID column:
class User extends Eloquent
{
/**
* The "booting" method of the model.
*
* @return void
*/
public static function boot() {
parent::boot();
static::deleting(function($user) {
$user->photos()->get(['id'])->each->delete();
});
}
}
2
votes
I would iterate through the collection detaching everything before deleting the object itself.
here's an example:
try {
$user = User::findOrFail($id);
if ($user->has('photos')) {
foreach ($user->photos as $photo) {
$user->photos()->detach($photo);
}
}
$user->delete();
return 'User deleted';
} catch (Exception $e) {
dd($e);
}
I know it is not automatic but it is very simple.
Another simple approach would be to provide the model with a method. Like this:
public function detach(){
try {
if ($this->has('photos')) {
foreach ($this->photos as $photo) {
$this->photos()->detach($photo);
}
}
} catch (Exception $e) {
dd($e);
}
}
Then you can simply call this where you need:
$user->detach();
$user->delete();
2
votes
Using Constrained()
After Laravel 7, new foreignId() and constrained() methods are available for defining relationship constraint in database. OnDelete() method can be used on these methods to automatically delete related records.
Old style
$table->unsignedBigInterer('user_id');
$table->foreign('user_id')
->references('id')
->on('users')
->onDelete('cascade');
New style
$table->foreignId('user_id')
->constrained()
->onDelete('cascade');
1
votes
In my case it was pretty simple because my database tables are InnoDB with foreign keys with Cascade on Delete.
So in this case if your photos table contains a foreign key reference for the user than all you have to do is to delete the hotel and the cleanup will be done by the Data Base, the data base will delete all the photos records from the data base.
0
votes
Or you can do this if you wanted, just another option:
try {
DB::connection()->pdo->beginTransaction();
$photos = Photo::where('user_id', '=', $user_id)->delete(); // Delete all photos for user
$user = Geofence::where('id', '=', $user_id)->delete(); // Delete users
DB::connection()->pdo->commit();
}catch(\Laravel\Database\Exception $e) {
DB::connection()->pdo->rollBack();
Log::exception($e);
}
Note if you are not using the default laravel db connection then you need to do the following:
DB::connection('connection_name')->pdo->beginTransaction();
DB::connection('connection_name')->pdo->commit();
DB::connection('connection_name')->pdo->rollBack();
-1
votes
yeah, but as @supersan stated upper in a comment, if you delete() on a QueryBuilder, the model event will not be fired, because we are not loading the model itself, then calling delete() on that model.
The events are fired only if we use the delete function on a Model Instance.
So, this beeing said:
if user->hasMany(post)
and if post->hasMany(tags)
in order to delete the post tags when deleting the user, we would have to iterate over $user->posts and calling $post->delete()
foreach($user->posts as $post) { $post->delete(); } -> this will fire the deleting event on Post
VS
$user->posts()->delete() -> this will not fire the deleting event on post because we do not actually load the Post Model (we only run a SQL like: DELETE * from posts where user_id = $user->id and thus, the Post model is not even loaded)
-2
votes
You can use this method as an alternative.
What will happen is that we take all the tables associated with the users table and delete the related data using looping
$tables = DB::select("
SELECT
TABLE_NAME,
COLUMN_NAME,
CONSTRAINT_NAME,
REFERENCED_TABLE_NAME,
REFERENCED_COLUMN_NAME
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE REFERENCED_TABLE_NAME = 'users'
");
foreach($tables as $table){
$table_name = $table->TABLE_NAME;
$column_name = $table->COLUMN_NAME;
DB::delete("delete from $table_name where $column_name = ?", [$id]);
}
