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16 March 2008 21:21

SQL Server 2008 - Whats this abut 30,000 columns?

Its all about Sparse columns and they are a great feature of Katmai Imagine you have a products table, you will have attributes for some products that don't apply to others i.e. cup size applies to bras but not to socks. There are a number of ways...
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20 July 2007 10:32

SQL Server The Truth - Rebuilding a clustered index does not rebuild the non clustered indexes

It used to be fact that the leaf page of a non-clustered index pointed to the row for the page, because it pointed to the file, page and row if the file or page of the row changed the nonclustered index had to be updated. Now however the non-clustered...
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26 June 2007 13:51

To cluster of not

Tony's blogged about the use of heaps http://sqlblogcasts.com/blogs/tonyrogerson/archive/2007/06/24/row-fragmentation-hopscotch-heap-v-clustered-and-io-cost.aspx . Whilst this highlights data on a page being out of sequence and thus yoyoing when you scan...
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04 April 2007 09:15

What is the cost of a query? Is it a beard?

I used to work on a project where we discussed what exactly the cost of a query was. You know that figured shown in execution plans. I knew it was used to age plans in a cache but not sure what unit it actually was. One of the guys on the project (Mike...
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16 March 2007 07:27

Online Index White Paper

Paul Randal recently informed me of a new white paper on online index operations. The whitepaper can be found here Online Index White Paper . This is one of many whitepapers that have been published lately by Bob Internals Troubleshooting ImplementingScaleOut...
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13 December 2006 09:16

When is full recovery mode not full recovery mode

I was recently trying to develop a test for DBAs. The scenario of the test was that you have taken over responsibility of a server what needs to be done to make it production ready. The server is really badly configured and the aim is for the tester to...
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16 November 2006 02:47

Checkpointing is now throttled in SQL 2005

During the iinterview with the SQLOS team this morning Slava mentioned that as part of the new design for the SQLOS the checkpoint process is much tightly controlled. If the checkpoint process has issues pages to be written and the latency has become...
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04 October 2006 08:00

SQL Engine - Storage of Large Object Data

If you are currently using text, ntext or image data in SQL 2000 and are looking to use "max" data types in SQL 2005 you will be interested in my first article for SQLServerCentral on the use of LOB data . The point I cover is the storage of data in and...
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