How do i get the sum of a row with the `GROUP BY` and also form all the rows without using `WITH ROLLUP`

The ERROR i get is Unknown column 'x' in 'field list'

Example

```
SELECT SUM(orderValue) as x GROUP BY day;

```

But that will only giv me the orderValue for each day, but i want to sum all the order as if i was not using GROUP BY. I know i can use ROLLUP but i need it in the SELECT.

Exmaple:

```
SELECT SUM(orderValue) as x, SUM(x) as total GROUP BY day;

ID  orderValue  day
--  ----------  ---
1   400         2015-01-01
2   800         2015-01-01
3   300         2015-01-01
4   400         2015-01-01
5   600         2015-01-01
6   500         2015-01-01
7   400         2015-01-02
8   800         2015-01-02
9   300         2015-01-02
10  400         2015-01-02
11  600         2015-01-02
12  500         2015-01-02

x       total
3000    6000
3000    6000

```