Saturday, February 25, 2012

DBCC DBREINDEX

Hi,
After runing this command on a table I noticed that logical scan
fragmentation increased.
I took a snapshot of the amount of fragementation before and after using
DBCC Showcontig and compared the results.
I would have expected the logical fragmentation to descrease.
Can someone please explain why this happened and would executing DBReindex
improve it.
CheersIf an index has very low fragmentation then rebuilding it can increase the
logical scan fragmentation because the layout of pages changes. Please read
the whitepaper below for more details.
http://www.microsoft.com/technet/prodtechnol/sql/2000/maintain/ss2kidbp.mspx
Regards.
--
Paul Randal
Dev Lead, Microsoft SQL Server Storage Engine
This posting is provided "AS IS" with no warranties, and confers no rights.
"mm" <postto@.news.com> wrote in message
news:uihGHJlWEHA.384@.TK2MSFTNGP10.phx.gbl...
> Hi,
> After runing this command on a table I noticed that logical scan
> fragmentation increased.
> I took a snapshot of the amount of fragementation before and after using
> DBCC Showcontig and compared the results.
> I would have expected the logical fragmentation to descrease.
> Can someone please explain why this happened and would executing DBReindex
> improve it.
> Cheers
>
>

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