Question

I m facing a problem to write a SQL query to get result in % mode, I am familer with SUM() and COUNT() functions of SQL Server but facing problem to implement logic inside query I want result in below form:-

UserName---  % of AccepectResult----   % of RejectResult

My table structure is like this with two columns Name (UserName) and Result :

NAME     Result
---------------
USer1       A
USer1       A
USer1       A
USer1       R
USer1       R
USer1       A
USer2       A
USer2       A
USer2       A
USer2       A
USer2       R

A - Accepted Result
R - Rejected Result

I’m trying to write this query like this..

select * into #t1  from 
(
    select UserName , count(Result) as Acc
    from Test where result = 'A'
    group by UserName 
) as tab1

select * into #t2 from 
(
    select UserName , count(Result) as Rej
    from Test where result = 'R'
    group by UserName 
) as tab2

select #t1.UserName , 
      #t1.Acc , 
      #t2.Rej , 
     (#t1.Acc)*100/(#t1.Acc + #t2.Rej)  as AccPercentage,
     (#t2.Rej)*100/(#t1.Acc + #t2.Rej)  as RejPercentage

 from #t1
 inner join #t2 on #t1.UserName = #t2.UserName


drop table #t1

drop table #t2

Is there any other way to write this query and any built-in function for calculating percentage in SQL Server?

Answer 1

You do not require to join table. Instead you can use SUM or COUNT function like this:

Using SUM Function:

SELECT Name, 100 * 
SUM(CASE WHEN Result = 'A' THEN 1 ELSE 0 END)/COUNT(result)
AS Accept_percent
,100 * 
SUM(CASE WHEN Result = 'R' THEN 1 ELSE 0 END)/COUNT(result)
AS Reject_percent
FROM t
Group by Name;

Or using COUNT Function:

SELECT Name, 100 * 
COUNT(CASE WHEN Result = 'A' THEN 1 ELSE NULL END)/COUNT(result)
AS Accept_percent
,100 * 
COUNT(CASE WHEN Result = 'R' THEN 1 ELSE NULL END)/COUNT(result)
AS Reject_percent
FROM t
Group by Name;

Or using SubQuery:

SELECT Name, 100 * 
(SELECT COUNT(result) FROM t WHERE result='A' And Name = main.Name)/COUNT(result)
AS Accept_percent
, 100 * 
(SELECT COUNT(result) FROM t WHERE result='R' And Name = main.Name)/COUNT(result)
AS Reject_percent 
FROM t main
Group by Name;

See this SQLFiddle