Blogs

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

on June 14, 2016 • 4 min read

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.

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

By Kendra Little on June 9, 2016 • 5 min read

Category: database-administration

Tags: dear-sql-dba , change-management , leadership

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

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

on June 7, 2016 • 6 min read

Category: database-administration

Tags: architecture , boundary-points , data-movement , merge , split , table-partitioning

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?

Lost in Performance Troubleshooting - Perf Triage for SQL Server

By Kendra Little on June 2, 2016 • 5 min read

Category: monitoring-troubleshooting

Tags: dear-sql-dba , wait-stats , sp-whoisactive , sp-blitz

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.

Testing an Insert for Race Conditions with Ostress.exe

on May 31, 2016 • 6 min read

Category: database-administration

Tags: concurrency , deadlocks , holdlock , insert , isolation , locking , ostress , ostress-exe , race-condition , stress-test , tsql , updlock

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.

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

By Kendra Little on May 26, 2016 • 4 min read

Category: database-administration

Tags: dear-sql-dba , upgrades , change-management

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.

The Case of the Blocking Merge Statement (LCK_M_RS_U locks)

on May 24, 2016 • 8 min read

Category: indexing

Tags: blocking , developer , holdlock , isolation-levels , key-range-locks , lck_m_rs_u , locking , merge , rs_u , serializable , tsql , performance-tuning

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.