sql-server - value return null row from query sql server

Question

Under SQL Server 2008, I want to return 0 value if there is no row found. I have tried my best but I failed. Please suggest me.

My requirement is:

myNullValue
-----------   
    0


SELECT (
        CASE 
            WHEN NoOfDue IS NULL
                THEN 0
            ELSE NoOfDue
            END
        ) myNullValue
FROM (
    SELECT COUNT(LHID) AS NoOfDue
    FROM dbo.TblLoanHistory
    WHERE (
            LHEMIPaid = 0
            OR LHEMIPaid IS NULL
            )
        AND LHAcNo = '010575100000114'
    GROUP BY LHEMI
    ) aa

Answer 1

select top 1 * from 
(
  SELECT COUNT(LHID) AS NoOfDue
  FROM dbo.TblLoanHistory 
  WHERE (LHEMIPaid=0 OR LHEMIPaid is null) 
  and LHAcNo='010575100000114' 
  GROUP BY LHEMI
  union 
  select 0 as NoOfDue
) x
order by NoOfDue