David Durant


Stairway to SQL Server Indexes

Deeper into Nonclustered Indexes: Stairway to SQL Server Indexes Level 2

By this stage, you should be familiar with the basics of SQL Server indexes. We've discussed what an Index actually is, as well as some of the most common types you're likely to encounter. Now that we've seen some simple examples of how Indexes can be useful, we're going to delve deeper into nonclustered indexes, as we'll see how they can improve the performance of more complex queries.

(3)

You rated this post out of 5. Change rating

2022-11-16 (first published: )

37,980 reads

Stairway to SQL Server Indexes

An Introduction to SQL Server Indexes: Stairway to SQL Server Indexes Level 1

Indexes are the database objects that enable SQL Server to satisfy each data access request from a client application with the minimum amount of effort, resulting in the maximum performance of individual requests while also reducing the impact of one request upon another. Prerequisites: Familiarity with the following relational database concepts: Table, row, primary key, foreign key

(1)

You rated this post out of 5. Change rating

2019-03-29 (first published: )

67,344 reads

Stairway to SQL Server Indexes

Pages and Extents: Stairway to SQL Server Indexes Level 4

We've now seen how indexed and non-indexed tables perform in queries, and established "logical reads" as the metric for query performance. Now it is time to explain why logical reads are an excellent metric and also explain what is actually being read.

(2)

You rated this post out of 5. Change rating

2019-03-29 (first published: )

19,226 reads

Blogs

AI: Blog a Day – Day 4: Transformers – Encoder, Decoder, and Attention

By

Continuing from Day 3 where we covered LLM models open/closed and their parameters, Today...

Flyway Tips: Multiple Projects

By

One of the nice things about Flyway Desktop is that it helps you manage...

What DevOps Look Like in Microsoft Fabric

By

Microsoft Fabric (not to be confused with the more general term “fabric” in DevOps)...

Read the latest Blogs

Forums

Can an Azure App Service Managed Identity be used for SQL Login?

By jasona.work

I'm fairly certain I know the answer to this from digging into it yesterday,...

Azure Synapse database refresh

By Sreevathsa Mandli

Hi Team, I am trying to refresh the Azure Synapse Dedicated pool from production...

how to write this query?

By water490

hi everyone I am not sure how to write the query that will produce...

Visit the forum

Question of the Day

Fun with JSON I

I have some data in a table:

CREATE TABLE #test_data
(
    id INT PRIMARY KEY,
    name VARCHAR(100),
    birth_date DATE
);

-- Step 2: Insert rows  
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT *
FROM OPENJSON(
     (
         SELECT t.* FROM #test_data AS t FOR JSON PATH
     )
             ) t;

See possible answers