Illuminate\Database\Query\Builder::orderByRaw PHP Method

    public function orderByRaw($sql, $bindings = [])
    {
        $property = $this->unions ? 'unionOrders' : 'orders';
        $type = 'raw';
        $this->{$property}[] = compact('type', 'sql');
        $this->addBinding($bindings, 'order');
        return $this;
    }

 /**
  * Scope to order by random.
  *
  * @param  \Illuminate\Database\Query\Builder $query
  * @return \Illuminate\Database\Query\Builder
  */
 public function scopeOrderByRandom($query)
 {
     static $randomFunctions = ['mysql' => 'RAND()', 'pgsql' => 'RANDOM()', 'sqlite' => 'RANDOM()', 'sqlsrv' => 'NEWID()'];
     $driver = $this->getConnection()->getDriverName();
     return $query->orderByRaw($randomFunctions[$driver]);
 }