SQLEspresso

Blog Post

Comparing Execution Plans

When you run a query twice, and get dramatically different run times, your first step can be to try to identify the differences in execution plans. For many that...

2019-07-05 (first published: )

930 reads

Blog Post

Filtered Index Basics

In this post, we continue with another beginner’s blog of database features that may be unknown to many. Let’s take a look at filtered indexes. Many database administrators are...

2019-06-10 (first published: )

767 reads

Blog Post

DMV’s for the Beginner

I give performance presentations at many different events to all levels of SQL Server professionals. Over time I’ve noticed that some DBAs and developers have never looked at the...

2019-05-29 (first published: )

2,097 reads

Blog Post

What is Implicit Conversion?

Another quick post of simple changes you can make to your code to create more optimal execution plans. This one is on implicit conversions. An implicit conversion is when...

2019-04-29 (first published: )

1,147 reads

Blog Post

What’s a Key Lookup?

One of the easiest things to fix when performance tuning queries are Key Lookups or RID Lookups. The key lookup operator occurs when the query optimizer performs an index...

2019-04-17 (first published: )

725 reads

Blog Post

Women in Tech Talk Tech

March is Women’s History Month, to celebrate the PASS Women in Technology Virtual Group (@PASS_WIT) held a webcast featuring prominent...

2019-04-09 (first published: )

1,036 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

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

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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...

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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