Question

Wonder if someone could give me a quick hand. I have 2 select queries (as shown below) and I want to compare the results of both and only return the result that has the most recent date.

So say I have the following 2 results from the queries:-

---------  ----------  -----------------------  ---------------  ------  --
COMPANY A  EMPLOYEE A  2007-10-16 17:10:21.000  E-mail 6D29D6D5  SYSTEM  1
COMPANY A  EMPLOYEE A  2007-10-15 17:10:21.000  E-mail 6D29D6D5  SYSTEM  1

I only want to return the result with the latest date (so the first one). I thought about putting the results into a temporary table and then querying that but just wondering if there’s a simpler, more efficient way?

SELECT * FROM (
    SELECT fc.accountidname, fc.owneridname, fap.actualend, fap.activitytypecodename, fap.createdby, fap.createdbyname,
    ROW_NUMBER() OVER (PARTITION BY fc.accountidname ORDER BY fap.actualend DESC) AS RN 
    FROM FilteredContact fc
    INNER JOIN FilteredActivityPointer fap ON fc.parentcustomerid = fap.regardingobjectid
    WHERE fc.statecodename = 'Active' 
        AND fap.ownerid = '0F995BDC' 
        AND fap.createdon < getdate()
) tmp WHERE RN = 1

SELECT * FROM (
    SELECT fa.name, fa.owneridname, fa.new_technicalaccountmanageridname, fa.new_customerid, fa.new_riskstatusname,  
    fa.new_numberofopencases, fa.new_numberofurgentopencases, fap.actualend, fap.activitytypecodename, fap.createdby, fap.createdbyname,
    ROW_NUMBER() OVER (PARTITION BY fa.name ORDER BY fap.actualend DESC) AS RN 
    FROM FilteredAccount fa 
    INNER JOIN FilteredActivityPointer fap ON fa.accountid = fap.regardingobjectid 
    WHERE fa.statecodename = 'Active' 
        AND fap.ownerid = '0F995BDC' 
        AND fap.createdon < getdate()
) tmp2 WHERE RN = 1

Answer 1

if the tables have the same structure (column count and column types to match), then you could just union the results of the two queries, then order by the date desc and then select the top 1.

select top 1 * from
(
   -- your first query
union all
   -- your second query.
) T
order by YourDateColumn1 desc