DBCC CHECKDB performance and computed-column indexes
[Edit 2016: The team ‘fixed’ the problem in SQL Server 2016 by skipping consistency checking these indexes unless WITH EXTENDED_LOGICAL_CHECKS is used.] It’s no secret that DBCC CHECKDB has some...
View ArticleOnline index rebuild corruption bug in SQL Server 2012 SP1
This is a quick blog post to let you know about a bug in SQL Server 2012 SP1 that can cause data loss when performing index maintenance. The data loss issue can happen in some circumstances when you do...
View ArticleAre mixed pages removed by an index rebuild?
This is a question that came up this morning during our IE1 class that I thought would make an interesting blog post as there are some twists to the answer. The first 8 pages that are allocated to an...
View ArticleHow would indexes on AG readable secondaries work?
Last weekend there was a suggestion on the MVP distribution list about having temporary nonclustered indexes on AG readable secondaries, in the same way that you can have temporary statistics on them....
View ArticleNew course: Index Fragmentation Internals, Analysis, and Solutions
My latest Pluralsight course has been published! It’s called SQL Server: Index Fragmentation Internals, Analysis, and Solutions and is just over 2.5 hours long. The modules are: Introduction Index...
View ArticleLow priority locking wait types
[Edit 2016: Check out my new resource – a comprehensive library of all wait types and latch classes – see here.] SQL Server 2014 (and Azure SQL Database V12) added some cool new functionality for...
View ArticleOn index key size, index depth, and performance
In my Insider newsletter a couple of weeks ago, I discussed how index fragmentation is often considered when designing indexes, but index depth often isn’t. In the newsletter I said I’d do a more...
View ArticleNew Pluralsight course: Indexing for Performance
It’s been a while coming but it’s worth the wait! Kimberly’s latest Pluralsight course has been published – SQL Server: Indexing for Performance – and it’s a monster 7 hours long and full of extensive...
View ArticleThe Curious Case of… extent scan fragmentation
(The Curious Case of… used to be part of our bi-weekly newsletter but we decided to make it a regular blog post instead so it can sometimes be more frequent. It covers something interesting one of us...
View ArticleThe Curious Case of… almost online index rebuilds
(The Curious Case of… used to be part of our bi-weekly newsletter but we decided to make it a regular blog post instead so it can sometimes be more frequent. It covers something interesting one of us...
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