Last entry on date for 2nd fields

[Raziyah00]

I have the following table to get the tapes marked +:

-------------------------------

FID | SID | DATE       | VAL

1 | 1 | 1997-08-12 | 'qwe' +
1 | 1 | 1997-07-14 | 'asd'
1 | 1 | 1997-06-15 | 'asd'
1 | 2 | 1997-08-06 | 'qwe' +
1 | 2 | 1997-07-11 | 'zxv'

So the last FID and SID records on the date. MSSQL.

[emerson]

Use the window function. row_number()♪ Start the window. partition by FID, SIDin which the lines are renumbered as specified order by Date desc♪ Then remove all lines with number one inside your window:

;with vTableName as (
    select
        rn = row_number()
            over (
                partition by FID, SID
                order by [Date] desc)
        , *
    from TableName
)
select *
from vTableName
where rn = 1;

Compared to type requests

select *
from <Таблица>
where not exists(select 1 from <Эта же таблица> where ...)

This approach reduces the number of IOs of operations, as the reference table is involved in the request One One.