SQLSTATE[42S22]: Column not found: 1054 Unknown column '0' in 'where clause' (SQL: select * from users where 0 = admin limit 1) - authentication

Question

I try to make login for admin using ajax.But I run into this error.I don't know where is column 0 come from.
SQLSTATE[42S22]: Column not found: 1054 Unknown column '0' in 'where
clause' (SQL: select * from users where 0 = admin limit 1)
Here is my code
public function login()
{
$username= Input::get('username');
$password= Input::get('password');
$admin=array([
'username'=>$username,
'password'=>$password,
'level'=>1
]);
if ($this->auth->attempt($admin)) {
return "ok";
}
else {
return "fail";
}
}
Model
<?php namespace App;
use Illuminate\Auth\Authenticatable;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Contracts\Auth\Authenticatable as AuthenticatableContract;
class User extends Model implements AuthenticatableContract
{
use Authenticatable;
/**
* The database table used by the model.
*
* #var string
*/
protected $table = 'users';
/**
* The attributes that are mass assignable.
*
* #var array
*/
protected $fillable = ["username","password",'level'];
/**
* The attributes excluded from the model's JSON form.
*
* #var array
*/
protected $hidden = ['password'];
public $timestamps = false;
}

Answer 1

The issue is your $admin array. You've mixed the two syntaxes for creating arrays and you've accidentally created an array of arrays.
You need to change your $admin array to either:
$admin = array(
'username'=>$username,
'password'=>$password,
'level'=>1
);
or:
$admin = [
'username'=>$username,
'password'=>$password,
'level'=>1
];