SELECT certain number of rows

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SELECT certain number of rows

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Jeff Moden SSC Guru Points: 1004406 More actions · Answer 1

Indexed multi-table view... multi-table SELECT... which one will you call UPDATEable? Neither in all likely hood. An update would have to be something separate... paging isn't used to update... 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Matt Miller (4) SSC Guru Points: 124210 More actions · Answer 2

Jeff Moden (3/13/2008)
Indexed multi-table view... multi-table SELECT... which one will you call UPDATEable? Neither in all likely hood. An update would have to be something separate... paging isn't used to update... 😉

Agreed. Just making sure:).

----------------------------------------------------------------------------------
Your lack of planning does not constitute an emergency on my part...unless you're my manager...or a director and above...or a really loud-spoken end-user..All right - what was my emergency again?

shamas saeed SSC-Addicted Points: 458 More actions · Answer 3

all possible ways are discussed above but think about

not in using top

select top 10 *

from table

where id not in (select top 20 id from table)

and cte

WITH Folder (IsUserFolder ,ParentFolderRowGUID ,RowGUID)

AS

(

SELECT *

FROM dbo.tblFolder AS P

whereRowGUID = @pRowGUID

UNION ALL

SELECT P.*

FROM dbo.tblFolder AS P

INNER JOIN Folder AS d

ON p.RowGUID = d.ParentFolderRowGUID

)

select top 1 * FROM Folder

where class filters the records

ChrisM@Work SSC Guru Points: 186127 More actions · Answer 4

Using Adam's sample data:

-- Top 21 TO 30 (less than one second)

SELECT TOP 10 * FROM (

SELECT TOP 30 * FROM dbo.TestData ORDER BY RowNum

) t ORDER BY RowNum DESC

-- Top 999,981 to 999,990 (one second)

SELECT TOP 10 * FROM (

SELECT TOP 999990 * FROM dbo.TestData ORDER BY RowNum

) t ORDER BY RowNum DESC

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden