Saturday, February 25, 2012

Data and index pages

As found in a book saying about Index pages:
'Unlike data pages, there is no limit to the total number of entries that
can be made on an index page.'
What is that mean ?It's wrong. An index page has the exact same limit as a data page. There's
8k in a page minus the header size and the slot array and that's all the
space that available on the page for records (entries). There's a finite
limit defined using the minimum possible record size plus the slot array
overhead for each record - I'd work it out for you exactly but I can't
remember the minimum possible record size off the top of my head. The max is
somewhere around 310-320 records per page though.
Regards
--
Paul Randal
Dev Lead, Microsoft SQL Server Storage Engine
This posting is provided "AS IS" with no warranties, and confers no rights.
"Alan" <NOSPAMalan_pltse@.yahoo.com.au> wrote in message
news:uXr6ainqEHA.1644@.tk2msftngp13.phx.gbl...
> As found in a book saying about Index pages:
> 'Unlike data pages, there is no limit to the total number of entries that
> can be made on an index page.'
> What is that mean ?
>

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