Blogs

Columnstore Index Returns Zero Rows... Which is One Row

I’ve never claimed to be great at math, but until recently I thought I knew how to count to one. Zero… one. That’s what we learned in kindergarten.

Apparently SQL Server didn’t go to kindergarten.

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Time for an Interview: What accomplishment are YOU most proud of?

Last week I answered a set of fun interview questions from Mohammad Darab. One question that he asked really jumped out at me:

What are you most proud of doing/accomplishing for the SQL Server community so far in your career?

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Using a Tail Log Backup in a SQL Server Migration (Dear SQL DBA Episode 34)

When you migrate a database, it can be useful to prove that you moved all the data and didn’t miss any transactions. Learn how to use a tail log backup in a migration scenario.

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Data Type Mismatches Do Not Always Cause a Bad Implicit Conversion and Index Scan

Here’s a great recent question that I got about query tuning and index use:

Assuming that the documented levels of data type precedence in SQL Server are true as of SQL 2016, why does a bigint value not force an index scan when compared against an int column?

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Why Indexes Reduce Locks for Update and Delete Queries

Indexes help queries run faster in SQL Server for several reasons. One of those reasons is that indexes can help your update and delete statements lock fewer rows. And I’m not only talking about shared locks, either.

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Stack Dumps in SQL Server (Dear SQL DBA Episode 33)

Learn what a Stack Dump is in SQL Server and watch a demo where I cause a stack dump against a test SQL Server instance under load. Learn how to find information about stack dumps on your SQL Server, and how to escalate them when required.

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Overindexing: Missing Index DMVs and the Database Tuning Advisor

SQL Server has tools that suggest indexes– and they’ll even auto-create the indexes for you.

I’m not a huge fan of these tools because they’ve got some notable flaws: they lead to creating more indexes than you need, and they aren’t super smart about the indexes they recommend.

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How to Quickly Tell if an Execution Plan has Multiple Missing Index Requests

Ever see those little green messages at the top of an execution plan?

Those are missing index suggestions.

SQL Server loves to suggest that you consider changing up your index game.

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New Course: Tuning Problem Queries in Table Partitioning

As of SQL Server 2016 SP1, you can now use partitioning in Standard, Web, and even Express Edition of SQL Server.

Everything’s gonna be fast! Right?

Well, not quite. But no worries, this course is now free.

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WAL: The concept that makes recovery models & backups make sense (Dear SQL DBA Episode 32)

When you’re a Junior DBA, it’s really hard to take in all the information out there.

Learn about write ahead logging: the concept that can help you make sense of recovery models and backup strategies in SQL Server. This is a foundational concept that helps you understand how SQL Server works.

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