Re: ghosted and forwarded records ?

From: Greg Linwood (g_linwoodQhotmail.com)
Date: 07/22/04 

Date: Thu, 22 Jul 2004 18:31:09 +1000

Hi Hassan

Ghosted records are records marked for lazy deletion by a system process.

Forwarded records only occur on tables without clustered indexes - "Heaps".
In the case where a row is updated so that it is wider & no longer fits on a
page, it is "forwarded" to another page & a forwarding marker left in its
original place. This helps avoid updating Non-Clustered Indexes (NCI) which
might be on the heap because NCIs on Heaps use File Page Row (FPR) pointers
on the leaf nodes. If forwarding records weren't used, indexe FPRs would
also need to be updated immediately upon such row updates when the row no
longer fits on the page it was on.

So, forwarding rows avoid needing to update FPRs on NCI leaf nodes when rows
are updated so they no longer fit on a page.

HTH

Regards,
Greg Linwood
SQL Server MVP

"Hassan" <fatima_ja@hotmail.com> wrote in message
news:%23SeSGl7bEHA.3580@TK2MSFTNGP11.phx.gbl...
> What are ghosted and forwarded records ?
>
>

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