sql查询另一列中给出的季度的季度百分比

Question

I have a Sales_Table

month  quarter   sales
1        1       100
2        1       200
3        1       300
4        2       400
5        2       500
6        2       600

I would like to have result for Quarterly percentage of sales(Quarterly column)

month  quarter   sales      Quarterly
1        1       100          17%
2        1       200          33%
3        1       300          50%
4        2       400          27%
5        2       500          33%
6        2       600          40%

I used the formula :
(Basically Quarterly = (sales*100/total of sales in same quarter)

And this is my query:

Select sales, month, quarter, sales * 100.0 / (select Sum(sales) from Sales_Table group by quarter) as quarterly
from Sales_Table
group by month;

This gives me result :

sales   month   quarter quarterly
100       1       1      16.666666666666668
200       2       1      33.333333333333336
300       3       1      50
400       4       2      66.66666666666667
500       5       2      83.33333333333333
600       6       2      100

This result shows correct quarterly value for quarter 1 but incorrect for quarter 2 .

Kindly help me for correct quarter 2 quarterly column values as well.

Answer 1

I would do the quarterly calculations in the from clause, using a subquery:

Select st.sales, st.month, st.quarter,
       (st.sales * 100.0 / q.sales) as quarterly
from Sales_Table st join
     (select quarter, sum(sales) as sales
      from Sales_Table
      group by quarter
     ) q
     on st.quarter = q.quarter;

If you want to format this as a percentage, then you can use:

concat(format(st.sales * 100.0 / q.sales, 2), '%')

Answer 2

http://sqlfiddle.com/#!9/454ba/6

SELECT s.sales, s.month, s.quarter, (s.sales * 100 / (q.q_sales)) as quarterly
FROM Sales_Table s
LEFT JOIN (
  SELECT quarter, SUM(sales) as q_sales
  FROM Sales_Table 
  GROUP BY quarter) as q
ON q.quarter = s.quarter

Answer 3

Your query with minimum editing:

 Select 
     sales, 
     month, 
     quarter, 
     sales * 100.0 / (select Sum(sales) from Sales_Table s WHERE s.quarter=m.quarter) as quarterly 
 from Sales_Table m

Answer 4

That's a non-scalar subquery. I suspect that MySQL is using one of the values at random just like it does when you reference a non-group-by column without an aggregate function. That would be why one is right and the other not. (And if you check the math you'll see that 600 was the divisor in all of the calculations.) I think you can fix your query by correlating on quarter .

select
    sales, month, quarter,
    sales * 100.0 / (
        select sum(sales) from Sales_Table st2
        where st2.quarter = st.quarter
        group by quarter
    ) as quarterly
from Sales_Table st

Actually you're also doing the whole non-aggregated column things that I mentioned when you group by month and then include sales and quarter in your output. In this case you don't need the group by anyway since all your rows are in their own group. But MySQL allows you to run that query where other platforms would have given you an error.