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laravel Eloquent ORM delete() method

Hi I am studying laravel. I use Eloquent ORM delete method but I get a different result.Not true or false but null. I set an resource route and there is a destroy method in UsersController.

public function destroy($id){

  $res=User::find($id)->delete();
  if ($res){
    $data=[
    'status'=>'1',
    'msg'=>'success'
  ];
  }else{
    $data=[
    'status'=>'0',
    'msg'=>'fail'
  ];
  return response()->json($data);

But I always get a response {"status":"0","msg":"failed"},the record in the database is deleted.

Then I use dd($res).It shows null in the page.

But from the course I learn it returns a boolean value true or false.

Is there any error in my code?

Can you tell me some other method that I can get a boolean result when I delete data from database?

我认为您可以更改您的查询并尝试如下:

$res=User::where('id',$id)->delete();

At first,

You should know that destroy() is correct method for removing an entity directly via object or model and delete() can only be called in query builder.

In your case, You have not checked if record exists in database or not. Record can only be deleted if exists.

So, You can do it like follows.

$user = User::find($id);
    if($user){
        $destroy = User::destroy(2);
    }

The value or $destroy above will be 0 or 1 on fail or success respectively. So, you can alter the $data array like:

if ($destroy){

    $data=[
        'status'=>'1',
        'msg'=>'success'
    ];

}else{

    $data=[
        'status'=>'0',
        'msg'=>'fail'
    ];

}

Hope, you understand.

Before delete , there are several methods in laravel.

User::find(1) and User::first() return an instance.

User::where('id',1)->get and User::all() return a collection of instance.

call delete on an model instance will returns true/false

$user=User::find(1);
$user->delete(); //returns true/false

call delete on a collection of instance will returns a number which represents the number of the records had been deleted

//assume you have 10 users, id from 1 to 10;
$result=User::where('id','<',11)->delete(); //returns 11 (the number of the records had been deleted)

//lets call delete again
$result2=User::where('id','<',11)->delete(); //returns 0 (we have already delete the id<11 users, so this time we delete nothing, the result should be the number of the records had been deleted(0)  ) 

Also there are other delete methods, you can call destroy as a model static method like below

$result=User::destroy(1,2,3);
$result=User::destroy([1,2,3]);
$result=User::destroy(collect([1, 2, 3]));
//these 3 statement do the same thing, delete id =1,2,3 users, returns the number of the records had been deleted

One more thing ,if you are new to laravel ,you can use php artisan tinker to see the result, which is more efficient and then dd($result) , print_r($result);

Laravel Eloquent provides destroy() function in which returns boolean value. So if a record exists on the database and deleted you'll get true otherwise false .

Here's an example using Laravel Tinker shell .

删除操作结果

In this case, your code should look like this:

public function destroy($id)
    {
        $res = User::destroy($id);
        if ($res) {
            return response()->json([
                'status' => 1,
                'msg' => 'success'
            ]);
        } else {
            return response()->json([
                'status' => 0,
                'msg' => 'fail'
            ]);
        }
    }

More info about Laravel Eloquent Deleting Models

$model=User::where('id',$id)->delete();

You can delete the data using two ways. First, using find Second, using where with model You can try something like this. First:

User::find($id)->destroy();

Or Second Way

User::where('id', $id)->delete();

Now Please try it will return you True/False result.

check before delete the user otherwise throws error exeption

$user=User::find($request->id);
  
   if($user)
   {
   // return $user;           <------------------------user exist
       if($user->delete()){
         return 'user deleted';
         }
    else{
       return "something wrong";
        }   

   }
  else{
     return "user not exist";// <--------------------user not exist
    }

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