Please have a look at the following query:
```
SELECT CS_Number,
Item_Num,
currency_code,
Stk_Code,
Stk_Desc,
sum(Stk_Qnty) AS CS_Stk_Quantity,
Selling_Price,
sum(Gross) AS Gross,
sum(Line_Tot) AS Line_Tot,
currency_code
FROM temp_cash_sale
WHERE cs_number = '01'
GROUP BY Stk_Code,
currency_code,
Selling_Price
ORDER BY Stk_Desc
```
The query is supposed to sum the (quantity sold, gross total, net total) and group by (stock_code, currency, price).
The issues here is the SQL query sometimes returns wrong results.
For example: Input
+-----------+-------------+---------------+----------+----------+----------+---------------+----------+
| cs_number | item_number | currency_code | stk_code | Stk_Desc | Stk_Qnty | Selling_Price | Line_Tot |
+-----------+-------------+---------------+----------+----------+----------+---------------+----------+
| 01 | 1 | USD | A001 | MILK | 2 | 5 | 10 |
| 01 | 2 | USD | A001 | MILK | 3 | 5 | 15 |
| 01 | 3 | USD | A001 | MILK | 1 | 4.5 | 4.5 |
| 01 | 4 | ZWL | A001 | MILK | 2 | 50 | 100 |
+-----------+-------------+---------------+----------+----------+----------+---------------+----------+
Expected output
+-----------+-------------+---------------+----------+----------+-----------------+---------------+----------+
| cs_number | item_number | currency_code | stk_code | Stk_Desc | CS_Stk_Quantity | Selling_Price | Line_Tot |
+-----------+-------------+---------------+----------+----------+-----------------+---------------+----------+
| 01 | 2 | USD | A001 | MILK | 5 | 5 | 25 |
| 01 | 3 | USD | A001 | MILK | 1 | 4.5 | 4.5 |
| 01 | 4 | ZWL | A001 | MILK | 2 | 50 | 100 |
+-----------+-------------+---------------+----------+----------+-----------------+---------------+----------+
If the above sql statement is wrong. Please assist me with the correct one
