Which is Worse: an Unused Index, or an Un-Indexed Foreign Key? (Dear SQL DBA Episode 16)
Category:
query-performance
Should you always index your foreign keys? What if you index them, and then the index never gets used?
Category: query-performance
Index Tuning Decision Tree for SQL Server
Category:
query-performance
I recently mapped out my thought process for how I approach a new instance of SQL Server when it comes to index tuning.
Unique Constraints vs Unique Indexes
Category:
query-performance
, sql-server
Unique constraints and unique nonclustered indexes have a lot in common: unique constraints are implemented with a unique index behind the scenes.
While unique nonclustered indexes have a couple of additional features, I can still think of a scenario where it might be best to use unique constraints.
Estimated vs. Actual Number of Rows in Nested Loop Operators
Category:
query-performance
, sql-server
This is one of those little details that confused me a ton when I was first working with execution plans.
One problem with learning to work with plans is that there’s just SO MUCH to look at. And it’s a bit spread out. So, even when looking at a single tooltip, things can be confusing.
Let’s talk about the nested loop operator, who can be particularly weird to understand.
Teach Yourself SQL Server Performance Tuning (Dear SQL DBA Episode 12)
Category:
query-performance
, sql-server
You’d love to have a job tuning SQL Servers, but you don’t have an environment to practice in. Here’s how to teach yourself performance tuning and prepare yourself to land and succeed in job interviews.
Why an Upgrade can Cause Performance Regressions (Dear SQL DBA Episode 9)
Category:
query-performance
, database-administration
You finally got approval to move to new hardware and a fresher version of SQL Server. After months of work, you do the migration and then… performance gets worse. What can cause this, and what do you look for?
Learn Index Tuning at the PASS Summit in 2016!
Category:
query-performance
I’m excited to announce that I’ll be giving a pre-conference session on index tuning, plus a general session on locking and blocking at the PASS Summit in Seattle this October! Here’s a description and a video to tell you all about these sessions.