SUM () function

I have 2 tables A and B.

A contains a column "AMOUNT"

B contains a column "ISSUEDAMOUNT" 

I want to get  the difference between total AMOUNT and total ISSUEDAMOUNT.

this should do the job

select Amount - ISSUEDAMOUNT from
(
(Select sum(AMOUNT) from tableA where (your where conditions)) as Amount ,
sum(ISSUEDAMOUNT) as ISSUEDAMOUNT
from tableB 
where (your where conditions)) 
) as Tempdata

This will help you

 select (select sum(AMOUNT) from TableA) - (select sum(ISSUEDAMOUNT) from
TableB) as 'Difference Amount'

Thanks Rajkamalr...........................................................

its working..........:) :) :)