A query is sometimes super fast and sometimes very slow. One of the main reasons for this problem is Parameter Sniffing. There are several approaches to addressing the Parameter Sniffing issue and this article discusses effective methods for handling Parameter Sniffing in SELECT statements containing a TOP clause.
2023-09-18
This is a short look at a technique that I discovered recently in Management Studio (SSMS). The technique is to compare two graphical execution plans in the tool to understand what they are doing and how two different queries might affect a particular system, both with the image and with the properties' data behind the […]
2021-03-30
4,356 reads
In this article we look at how to interpret and use the results of STATISTICS IO when tuning SQL Server queries.
2021-02-17
There are plenty of experts that look to teach you about query tuning and the internals of query execution in SQL Server.
2020-07-18
150 reads
In this article we look at different use cases for columnstore indexes like when performing SQL Server count * queries.
2020-01-17
As SQL developers, we tend to think of performance tuning in terms of crafting the best table indices, avoiding scalar and table valued functions, and analyzing query plans (among other things). But sometimes going back to the spec and applying some properties of elementary math can be the best way to begin to improve performance of SQL queries which implement mathematical formulas. This article is a case study of how I used this technique to optimize my SQL implementation of the Inverse Simpson Index.
2021-05-07 (first published: 2019-09-12)
5,309 reads
Introduction Instead of going straight into the topic of the Query Store, I would like to start this Stairway Series by mentioning a few performance tuning scenarios that are very common to production DBAs. I think most of us have been in one of these situations at some time: An application experiencing slowness after a […]
2020-10-07 (first published: 2019-05-13)
6,212 reads
The IGNORE_DUP_KEY option for unique indexes specifies how SQL Server responds to an attempt to INSERT duplicate values: It only applies to tables (not views) and only to inserts. Any insert portion of a MERGE statement ignores any IGNORE_DUP_KEY index setting.
2019-04-05
Far too often, an indexed view is created without consideration for the costs of the indexed view. In this article, Jason Brimhall covers some of the more important costs that are frequently overlooked when considering an indexed view as a performance panacea.
2019-04-05
Kevin Feasel provides three SSMS keyboard shortcuts for the sp_whoisactive calls he uses most often in day-to-day database development and query tuning work.
2019-04-02
You can find the slides for my session at Future Data Driven summit at...
By Steve Jones
I saw someone limit the databases they see in SSMS, which isn’t something I...
Since witnessing a rather nasty cyber attack around a year ago, I’ve been thinking...
Hi all, I have an SQL database table with events, and within it a...
Hi All, I have been trying to download a csv file which is produced...
Hi We have an stored procedure which runs frequently and it contain logic in...
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