在T-SQL的销售总额中，销售收入的80％

Question

I have data like this

Brand Name  Sales Cost  Mkt
Brand1  3312    ABC
Brand2  3490    ABC
Brand3  7794    ABC
Brand4  8325    ABC
Brand5  3915    ABC
Brand6  6494    ABC

Expected output should be like this:

Brand Name  Sales Cost  Mkt Percentage
Brand1  3312    ABC 10%
Brand2  3490    ABC 17%
Brand3  7794    ABC 80%
Brand4  8325    ABC 89%
Brand5  3915    ABC 12%
Brand6  6494    ABC 59%

I want to find out Brand that holds 80% sales in ABC market? Suggestions please

Answer 1

I guess you want window functions. I'm assuming that brandX can occur more than once in your data for one mkt (even though you do not have such rows in your example)

select brand, 
       mkt,
       sum(sales), 
       sum(cast(sales as float))/sum(cast(sum(sales) as float)) over (partition by mkt) * 100 
from data
group by brand, mkt

dbfiddle demo

and if you want those having more then 80% use subquery and where

select *
from
(
    select brand, 
           mkt,
           sum(sales) sumsales, 
           sum(cast(sales as float))/sum(cast(sum(sales) as float)) over (partition by mkt) * 100 percentsales
    from data
    group by brand, mkt
) t
where percentsales > 80

Answer 2

Try this:

select * from (
select [Brand Name],
       [Sales],
       [Cost],
       [Sales]/(sum([Sales]) over (partition by (select null))) [Mkt Percentage]
from MY_TABLE
) [a] where [Mkt Percentage] >= 0.8