如何在MySQL中没有总计子句的情况下在MySQL中计算总计

Question

i want to get grand total of a column without using group by clause as i don't want to concat any string.

i looking for this kind desired result:

|  customer id | project name | Product Name | Quantity | price  | total    |
+--------------+--------------+--------------+----------+--------+----------+
|     9        |  xyz         |   ppn        |   2      |   2    |   4      |
+--------------+--------------+--------------+----------+--------+----------+
|    11        |    pqr       |    xxx       |    2     |   2    |    4     |
+--------------+--------------+--------------+----------+--------+----------+
|              |              |              |          |        |     8    |<=== Grand total  
+---------------------------------------------------------------------------+

here is SQL Fiddle: http://sqlfiddle.com/#!9/30fdd5/2

Answer 1

I think this does what you want:

SELECT customer_id, project_name, product_name, quantity,
       price, quantity * price as total 
FROM project_expenses_data
UNION ALL
SELECT NULL, NULL, NULL, NULL, NULL, sum(quantity * price)
FROM project_expenses_data;

To be 100% clear that the total is the last row in the result set, add the clause ORDER BY (customer_id IS NULL) ASC .