Clik here to view.
How Parallel Plans Start Up – Part 3
This is the third in a five-part series taking a deep dive into the way SQL Server row mode parallel plans start executing. Part 1 initialized execution context zero for the parent task, and part 2...
View ArticleIntroduction to Latches
In some of my previous articles here on performance tuning, I’ve discussed multiple wait types and how they are indicative of various resource bottlenecks. I’m starting a new series on scenarios where...
View ArticleClik here to view.
How Parallel Plans Start Up – Part 4
This is the fourth part in a five-part series taking a deep dive into the way SQL Server row mode parallel plans start executing. Part 1 initialized execution context zero for the parent task, and part...
View ArticleClik here to view.
Number series generator challenge solutions – Part 5
.warnHigh { color:#ff2200!important; } This is the fifth and last part in the series covering solutions to the number series generator challenge. In Part 1, Part 2, Part 3 and Part 4 I covered pure...
View ArticleClik here to view.
How Parallel Plans Start Up – Part 5
This is the final part of a five-part series taking a deep dive into the way SQL Server row mode parallel plans start executing. Part 1 initialized execution context zero for the parent task, and part...
View ArticleClik here to view.
Foreign Keys, Blocking, and Update Conflicts
Most databases should make use of foreign keys to enforce referential integrity (RI) wherever possible. However, there is more to this decision than simply deciding to use FK constraints and creating...
View ArticleClik here to view.
The FGCB_ADD_REMOVE Latch
In my previous article I kicked off a new series on latches by explain what they are, why they’re needed, and the mechanics of how they work, and I strongly recommend that you read that article before...
View ArticleClik here to view.
Deprecated features to take out of your toolbox – Part 3
ul.h, ul.w { margin:11px 22px!important; } ul.h li { display:inline-block; padding:9px 24px;font-family:Montserrat!important;font-weight:bold;font-size:1.125em;color:#444!important; } ul.h li:before {...
View ArticleClik here to view.
UI Design Patterns That Don't Scale
Guest Author : Michael J Swart (@MJSwart) I spend a large amount of time translating software requirements into schema and queries. These requirements are sometimes easy to implement but are often...
View ArticleThe DBCC_OBJECT_METADATA Latch
Continuing my series of articles on latches, this time I’m going to discuss the DBCC_OBJECT_METADATA latch and show how it can be a major bottleneck for consistency checks prior to SQL Server 2016...
View ArticleThe APPEND_ONLY_STORAGE_INSERT_POINT Latch
Continuing my series of articles on latches, this time I’m going to discuss the APPEND_ONLY_STORAGE_INSERT_POINT latch and show how it can be a major bottleneck for heavy update workloads where either...
View ArticleClik here to view.
Split strings the right way – or the next best way
UPDATE: September 2nd, 2021 (Originally published July 26th, 2012.) A lot of things change over the course of a few major versions of our favorite database platform. SQL Server 2016 brought us...
View ArticleSQL Server Latches – Other Latches To Know About
To finish up my short series of articles on latches, this time I’m going to discuss a few other latches in SQL Server you might see occasionally but don’t merit a complete article by themselves. As...
View ArticleRefreshing SQL Server Tables With Less Interruption Using Partition Switching
A common requirement in ETL and various reporting scenarios is to quietly load a SQL Server staging table in the background, so users querying the data aren’t impacted by the writes and vice-versa. The...
View ArticleClik here to view.
Tracking Synchronous Statistics Updates
Introduction The SQL Server query optimizer makes use of statistics during query compilation to help determine the optimal query plan. By default, if the optimizer notices a statistic is out-of-date...
View ArticleClik here to view.
The Adaptive Join Threshold
First introduced in SQL Server 2017 Enterprise Edition, an adaptive join enables a runtime transition from a batch mode hash join to a row mode correlated nested loops indexed join (apply) at runtime....
View ArticleClik here to view.
Matching Supply With Demand Challenge
My friend Peter Larsson sent me a T-SQL challenge involving matching supply with demand. As far as challenges go, it's a formidable one. It's a pretty common need in real life; it's simple to describe,...
View ArticleClik here to view.
Matching Supply With Demand — Solutions, Part 1
Last month, I covered Peter Larsson's puzzle of matching supply with demand. I showed Peter's straightforward cursor-based solution and explained that it has linear scaling. The challenge I left you...
View ArticleThe SQL Server Transaction Log, Part 1: Logging Basics
All through my career as a data professional, both inside Microsoft and as a consultant, I’ve found one of the most misunderstood parts of a SQL Server database is the transaction log. Lack of...
View ArticleClik here to view.
Matching Supply With Demand — Solutions, Part 2
[ Jump to: Original challenge | Solutions: Part 1 | Part 2 ] In this article, I continue the coverage of solutions to Peter Larsson’s enticing matching supply with demand challenge. Thanks again to...
View Article