Implement paging (skip / take) functionality with this query

I have been trying to understand a little bit about how to implement custom paging in SQL, for instance reading articles like this one.

I have the following query, which works perfectly. But I would like to implement paging with this one.

SELECT TOP x PostId FROM ( SELECT PostId, MAX (Datemade) as LastDate
 from dbForumEntry 
 group by PostId ) SubQueryAlias
 order by LastDate desc

What is it I want

I have forum posts, with related entries. I want to get the posts with the latest added entries, so I can select the recently debated posts.

Now, I want to be able to get the "top 10 to 20 recently active posts", instead of "top 10".

What have I tried

I have tried to implement the ROW functions as the one in the article, but really with no luck.

Any ideas how to implement it?

In SQL Server 2012 it is very very easy

SELECT col1, col2, ...
 FROM ...
 WHERE ... 
 ORDER BY -- this is a MUST there must be ORDER BY statement
-- the paging comes here
OFFSET     10 ROWS       -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows

If we want to skip ORDER BY we can use

SELECT col1, col2, ...
  ...
 ORDER BY CURRENT_TIMESTAMP
OFFSET     10 ROWS       -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows

(I'd rather mark that as a hack - but it's used, e.g. by NHibernate. To use a wisely picked up column as ORDER BY is preferred way)

to answer the question:

--SQL SERVER 2012
SELECT PostId FROM 
        ( SELECT PostId, MAX (Datemade) as LastDate
            from dbForumEntry 
            group by PostId 
        ) SubQueryAlias
 order by LastDate desc
OFFSET 10 ROWS -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows

New key words offset and fetch next (just following SQL standards) were introduced.

But I guess, that you are not using SQL Server 2012, right? In previous version it is a bit (little bit) difficult. Here is comparison and examples for all SQL server versions: here

So, this could work in SQL Server 2008:

-- SQL SERVER 2008
DECLARE @Start INT
DECLARE @End INT
SELECT @Start = 10,@End = 20;


;WITH PostCTE AS 
 ( SELECT PostId, MAX (Datemade) as LastDate
   ,ROW_NUMBER() OVER (ORDER BY PostId) AS RowNumber
   from dbForumEntry 
   group by PostId 
 )
SELECT PostId, LastDate
FROM PostCTE
WHERE RowNumber > @Start AND RowNumber <= @End
ORDER BY PostId

In order to do this in SQL Server, you must order the query by a column, so you can specify the rows you want.

Example:

select * from table order by [some_column] 
offset 10 rows
FETCH NEXT 10 rows only

And you can't use the "TOP" keyword when doing this.

You can learn more here: https://technet.microsoft.com/pt-br/library/gg699618%28v=sql.110%29.aspx

SQL 2008

Radim Köhler's answer works, but here is a shorter version:

select top 20 * from
(
select *,
ROW_NUMBER() OVER (ORDER BY columnid) AS ROW_NUM
from tablename
) x
where ROW_NUM>10

Source: https://forums.asp.net/post/4033909.aspx

OFFSET     10 ROWS       -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows

use this in the end of your select syntax. =)

Implement paging (skip / take) functionality with this query

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