Question

I am supposed to build a query that displays if a product passed quality test the first time. for example if product# 1234 fails the first test then don’t display the value. I am running SQL Server 2005. I am thinking maybe using a COALESCE statement, or case when statement, any help would be appreciated. here is some sample data:

product#  test result   datetime
1102494    Fail         20111129:07:57:50.203
1102494    pass         20111130:16:48:28.140
1102496    pass         20111129:11:09:32.140
1102498    pass         20111129:08:21:10.218

Answer 1

Show only the first result, and only if the first result is a ‘pass’.

select *
  from (
select *, rn=row_number() over (partition by [product#] order by [datetime] desc)
  from tests
     ) x
 where rn=1 and result = 'pass';