Blogs

Outside the Big SAN Box: Identifying Storage and SAN Latency in SQL Server (Dear SQL DBA)

Dear SQL DBA, What do you say to a SAN admin when you think that the billion dollar SAN *may* be the bottleneck and you just want to look into it. What are the technical things I need to say to make them believe there might be something to my questions?

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Target Recovery Interval and Indirect Checkpoint - New Default of 60 Seconds in SQL Server 2016

Update, 6/21/2016: Be careful using indirect checkpoint with failover clusters if your SQL Server 2014 instance is not fully patched. See KB 3166902. This bug was fixed in SQL Server 2016 prior to RTM.

SQL Server 2016 introduces big new features, but it also includes small improvements as well. Many of these features are described in the “It Just Runs Faster” series of blog posts by Bob Ward and Bob Dorr.

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Next Door to Derpton - When Your Fellow DBA is a Danger to Databases (Dear SQL DBA)

What do you do when your fellow DBA is a ticking time-bomb of bad decisions, waiting to explode your production environment?

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Merging Boundary Points: Does a Changing Partition_Number Indicate Data Movement?

I received a question from a reader who was testing out a partitioning architecture:

We are testing table partitioning using one filegroup per partition. When we merge a boundary point, we see that partition_number changes in sys.partitions. Does this mean that data movement is occurring?

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Lost in Performance Troubleshooting - Perf Triage for SQL Server

Psssttt – I have an updated blog post on this called the Learner’s Guide to SQL Server Performance Tuning

The SQL Server is slow, what should you do? I answer a reader question and share my strategy for performance troubleshooting.

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Testing an Insert for Race Conditions with Ostress.exe

Whenever we have multiple sessions modifying data, things get tricky. When we have a pattern of “check if the data exists and then do a thing,” multiple sessions get even more complicated.

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Bleeding In Edgeville - When Upgrades Come Too Fast (Dear SQL DBA)

In this episode of “Dear SQL DBA,” I answer a question about early adoption of SQL Server, discuss why testing in production isn’t necessarily crazy, and recommend how to handle requests to upgrade your SQL Server to use new features.

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The Case of the Blocking Merge Statement (LCK_M_RS_U locks)

Recently I got a fun question about an “upsert” pattern as a “Dear SQL DBA” question. The question is about TSQL, so it lent itself to being answered in a blog post where I can show repro code and screenshots.

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Blogger Tip: Easy Free-Use Images with Pablo by Buffer

I’ve gotten a few compliments lately on the images I’ve been using in my posts. Images help engage your readers. You should also set a “featured image” for each post for thumbnail usage in your theme or in RSS readers. But it can be kind of a pain to search for images and make sure the image copyright allows you to use and share it.

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Index Usage Stats Bug Fixed in SQL Server 2012 SP2 CU12 / SP3 CU3

Microsoft has just released a new round of cumulative updates for SQL Server 2012, and the release notes indicate that a fix to the sys.dm_db_index_usage_stats dynamic management view has been included in these updates. This is good news for index tuners using SQL Server 2012.

As of SP2 + CU12 and SP3 + CU3, SQL Server 2012 will persist index usage information even when ALTER INDEX REBUILD is run.

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