Posts by Tara Kizer

How to Reduce the CPU Overhead of Dynamic SQL

Development, T-SQL
14 Comments
Dynamic SQL is a good choice for catch-all type queries, but you have to be careful how you execute the dynamic string. For frequently executed queries, “EXEC sp_executesql @sql”is a good choice but at the risk of encountering parameter sniffing issues. For queries that aren’t executed very often, “EXEC (@sql)” can be used, but you…
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Concurrency Week: How Entity Framework and NHibernate Can Cause Poison RESOURCE_SEMAPHORE Waits

Development, Memory Grants
6 Comments
I’ve already blogged about my dislike for ORMs from a production DBA performance tuning standpoint only. I get that they’re useful to developers. I get it. But I’m focused on performance. A quick recap of what I don’t like about ORMs from that other blog post: Implicit conversions due to nvarchar variables vs varchar columns…
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Network Issue or THREADPOOL waits?

Wait Stats
10 Comments
I’ve had a handful of clients that were experiencing significant THREADPOOL waits. This isn’t a wait type that I had any knowledge of prior to joining Brent Ozar Unlimited. Looking back, I am pretty sure that a few servers that I’ve been responsible for over the years were experiencing it based on the symptoms. WebOps:…
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Maintenance Plans Enable Your Disabled Indexes

SQL Server
6 Comments
One of Brent’s students in the Performance Tuning class, Jason M., told Brent that maintenance plans enable your disabled indexes. What the what? Steps to reproduce: Disable an index Setup a maintenance plan to rebuild all indexes Run the job Check if the index is disabled or enabled. Steps 1 and 2 can be reversed…
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Index Maintenance Madness

SQL Server
36 Comments
When we look at a new server, we check out their database maintenance jobs, making sure their server is in a safe place before we dig into their pain points. We verify if their backups and DBCC CHECKDB jobs can meet their RPO/RTO goals. We also check out their index maintenance jobs, if any. When…
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What Do You Think About ORMs?

Development
26 Comments
I was recently asked what I thought about ORMs (Entity Framework, NHibernate, Dapper, etc) while we were looking at implicit conversion warnings in execution plans. Before I answered the question, I let them know that my answer is based on being a production DBA and the numerous performance problems I have had to troubleshoot that…
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New White Paper: How to Build a SQL Server Disaster Recovery Plan with Google Compute Engine

You’re a systems administrator or database administrator who wants to protect your production SQL Server. However, you don’t have a separate data center or another colo site. Learn about what we call Log Shipping 2.0 You’re looking for instructions on: How to copy your SQL Server databases to Google Cloud Storage How to spin up…
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