While preparing for my SQL Saturday Salt Lake City presentation, Climbing the B-Tree, I ran into one of the “word of mouth” facts that the first column of an index should be highly selective, i.e., it should only point to one or a few rows. This is not always the case and I’ll show you […]
2023-01-02 (first published: 2020-09-16)
5,683 reads
In the last year I’ve published articles on indexes to include Indexes: When Column Selectivity Is Not Always A Requirement – SQLServerCentral and Query Optimizer Suggests Wrong Index and Query Plan -- Why? – SQLServerCentral. This article is a continuation of just how the optimizer interacts with the index wizard. We’ve all heard and read […]
2021-07-07
3,885 reads
A good example where the Query optimizer picks the wrong query plan and suggested index.
2021-02-25
5,224 reads
Continued analysis of index architecture with revised clustered index. Part 2 of Column Order Indexes
2020-12-11 (first published: 2019-04-24)
2,649 reads
Ever wonder about index column order; this piece should give some insight.
2020-12-04 (first published: 2019-02-28)
9,020 reads
Is there a difference between using TOP and MAX/MIN to return and end value to a table?
2020-08-14 (first published: 2018-12-17)
7,966 reads
In Part 1 of this article we looked at a specific use case (probably exaggerated) that gave us an idea about how CPU and IO performance might be affected by a bad page split. We continue this analysis looking at what really happens to the data on the leaf pages of a clustered index with […]
2020-07-02
4,554 reads
2020-03-03 (first published: 2019-11-25)
10,778 reads
Introduction Fill Factor is a parameter most of us have ignored because there is no definitive way to calculate what the correct value should be. Part 1 of this series describes a new technique to dynamically determine index fill factors for all indexes within a database. Part 2 covers an analysis of the data collection […]
2019-08-27
4,024 reads
Introduction So what’s all the fuss about Fill Factor? It is a SQL Server parameter I’ve ignored for 20+ years. The main reason was/is I’ve had no idea about what value to use. There is just no documented definitive guidance. Back in April at SQL Saturday #830 - Colorado Springs, I attended two sessions by […]
2019-08-20
9,153 reads
By Steve Jones
This is timely, as I’m currently on a boat in the Adriatic taking a...
You can find the slides and SQL scripts for my session “Spice up your...
By SQLPals
How to Clear the SSMS Cache (SSMS 21 and Later) Updated...
Comments posted to this topic are about the item Using CHOOSE()
Comments posted to this topic are about the item Re-Seeding a Broken Log Shipping...
Comments posted to this topic are about the item The DBA is Dead! Long...
We have this code that sets some status values and then queries them using the CHOOSE() function in SQL Server 2025.
CREATE TABLE Status
(
StatusID INT,
StatusDescription VARCHAR(20)
);
GO
INSERT dbo.Status
(
StatusID,
StatusDescription
)
VALUES
(0, 'Uncategorized'),
(1, 'Active'),
(2, 'Inactive'),
(3, 'Temp');
GO
SELECT CHOOSE(StatusID, 'Unknown', 'Active', 'Inactive', 'Temporary')
FROM Status;
When the SELECT runs, what is returned? See possible answers