how long it takes to retrieve top 10000 records

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how long it takes to retrieve top 10000 records

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Phil Parkin SSC Guru Points: 245813 More actions · Answer 1

Sean Lange (7/25/2012)

Phil Parkin (7/25/2012)

Nice article - thanks for the link. When I read absolutes (like 'meaningless') my brain subconsciously challenges them. I still think it was the wrong word 🙂

Maybe it could be reworded, albeit a bit more lengthy to something like: "Using top without an order by is like saying, Get me the first N rows that the engine feels is the easiest to retrieve". 🙂

So that would make it not meaningless and more accurate. The worst part is that it is most likely going to be consistent for a certain amount of data but will change at some point when sql decides it is easier to get some other rows.

Sean - I think you've nailed it.

If you haven't even tried to resolve your issue, please don't expect the hard-working volunteers here to waste their time providing links to answers which you could easily have found yourself.

krishna.netblogs SSC Veteran Points: 244 More actions · Answer 2

krishna.netblogs

SSC Veteran

Points: 244

July 26, 2012 at 12:25 am

#1517741

Hi

ChrisM@Work,

Thanks for your reply/some valuable points about indexing.

so the order by column(s) should have indexed to improve performance.

Thanks

Krishna

krishna.netblogs SSC Veteran Points: 244 More actions · Answer 3

krishna.netblogs

SSC Veteran

Points: 244

July 26, 2012 at 12:28 am

#1517742

Hi

anthony.green

Thanks for your response.

Can you bit give some more information about access methods and blocking that you mentioned .

With Regards

Krishna

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

Sean Lange (7/25/2012)

Phil Parkin (7/25/2012)

Nice article - thanks for the link. When I read absolutes (like 'meaningless') my brain subconsciously challenges them. I still think it was the wrong word 🙂

Maybe it could be reworded, albeit a bit more lengthy to something like: "Using top without an order by is like saying, Get me the first N rows that the engine feels is the easiest to retrieve". 🙂

So that would make it not meaningless and more accurate. The worst part is that it is most likely going to be consistent for a certain amount of data but will change at some point when sql decides it is easier to get some other rows.

Nice one, Sean. I like this a lot.

^{“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

Sean Lange SSC Guru Points: 286562 More actions · Answer 5

ChrisM@Work (7/26/2012)

Sean Lange (7/25/2012)

Phil Parkin (7/25/2012)

Nice article - thanks for the link. When I read absolutes (like 'meaningless') my brain subconsciously challenges them. I still think it was the wrong word 🙂

Maybe it could be reworded, albeit a bit more lengthy to something like: "Using top without an order by is like saying, Get me the first N rows that the engine feels is the easiest to retrieve". 🙂

So that would make it not meaningless and more accurate. The worst part is that it is most likely going to be consistent for a certain amount of data but will change at some point when sql decides it is easier to get some other rows.

Nice one, Sean. I like this a lot.

hehe.

While it is more descriptive your version is a lot easier to roll off the keyboard. 😉

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