The Bit Bucket

So 2025 is done. It was both an interesting and a challenging year for me. I’m so glad for all you who have been reading my blog and hope you’ll continue into the future.

What Will Matter Most for Data Professionals in 2026?

As a new year begins, it’s a good time to pause and look ahead — not with hype or predictions, but with a practical view of what will genuinely matter for data professionals in 2026. Across consulting projects, training course development, and hands-on work with SQL Server, Microsoft Fabric, and modern data platforms, several patterns have emerged that are shaping how teams build and operate data solutions.

2026-01-01

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Intro

Question:

You are using Object Explorer in SQL Server Management Studio (SSMS) to browse the contents of a SQL Server. In the System Databases folder, there is a database named model. What is its purpose?

2025-12-31

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Development Level: Medium

Question:

Does a stored procedure automatically provide a transaction i.e., if a statement within a stored procedure fails, are all previous data modification statements rolled back?

Answer:

No, a stored procedure does not automatically provide an implicit transaction.

2025-12-30

I’ve attended a lot of user groups over the years. They’ve been data-related, developer-related, and all sorts of other topics. I’ve also organized a lot of user groups over the years. One problem that I fell into early on, and that I see many others falling into, is the problem of increasing depth.

User group leaders often have a very skewed view of the content that’s been presented at their groups. That’s because they’ve often seen almost every single presentation that’s ever been given.

2025-12-29

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Advanced

Question:

When checkpoint writes occur, is only committed data written, or is uncommitted data written?

If only committed data, explain why.

If both, explain why.

Answer:

Checkpoint is a background process that:

• Flushes dirty pages (pages in memory that have been modified since they were read from disk) to disk.
• Records a log sequence number (LSN) in the transaction log that marks the point at which the database is known to be consistent on disk.

This means that SQL Server doesn’t flush only committed transactions — it flushes all dirty pages, whether the transactions that modified them are committed or not.

2025-12-28

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Advanced

Question:

You know that the master database in SQL Server is now separate to the resource database (mssqlsystemresource).

Can you list three types of instance-level metadata that still live in the master database?

Answer:

2025-12-27

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Medium

Question:

If you have successfully created a SQL Server database backup, what could cause you to not be able to restore it, on the same server or another server ?

Answer:

A successful SQL Server backup does not guarantee that it can later be restored successfully. A few important points explain why:

2025-12-26

2025 has been a busy and challenging year for me. I want to thank all of you who have been reading my blog. Every week, there are more views than before. I’m pleased to see that, even when I’ve been posting daily.

Whatever your belief system, Christmas is a moment of pause for many of us, but it’s also a reminder of how much data shapes the world around us — even in the stories we grew up with.

2025-12-25

Execution plans are one of the most valuable tools in SQL Server for understanding how a query is executed. But even experienced developers and DBAs regularly misinterpret certain operators. Some of these operators look deceptively simple, others have subtle side effects, and a few behave differently depending on cardinality estimates or memory availability.

This post walks through the execution plan operators that are most frequently misunderstood, what they actually mean, and how to interpret them correctly.

2025-12-24

More SQL love !

Creating reports, analytics, or applications? And need to get data out of Oracle? Learn to write SQL queries like a pro !

We have very popular SQL courses, for T-SQL, PostgreSQL, Snowflake, and MySQL. We’ve just added our new course Writing SQL Queries for Oracle and you can enrol in it now. It’s already low cost but even better, if you use the coupon code HNY2026 at checkout before 5th January, you can take advantage of our Happy New Year 25% discount as well.

2025-12-23