There is a really common misconception about output order for T-SQL queries. I can’t tell you how often I’ve heard people say that if you don’t specify an ORDER BY clause, then you’ll see the rows returned in the order of the primary key.
The assumption they’re also making is that the primary key is the clustering key. And that’s not necessarily true either. You can have a non-clustered primary key on a table.
2025-08-02
Everyone who’s worked with SQL Server for any length of time, has had the experience of executing a T-SQL script, and then noticing, with horror, that they’ve just executed the script against the wrong server.
You know the feeling. It even happens at Christmas time, just when you were hoping to get away from work for a few days, or when you are the unlucky one who’s doing on call work.
2025-08-01
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: Advanced
Question:
A storage failure occurs and during recovery, a data file from your database was lost.
Transaction log backups are taken every 5 minutes.
Periodically, when data is being loaded into the database, Bulk Logged mode is used. At the time of the failure, the database was still in bulk logged mode.
2025-07-31
When I am writing my own code using a .NET (or other) language, I have a great deal of control of how the connection string that my application uses to connect to SQL Server is configured.
In particular, I might need to add another parameter or two.
As a simple example, I might be working with a multi-subnet Availability Group, spread across a production site and a disaster recovery site. It’s common to then have an Availability Group Listener in both subnets.
2025-07-30
In previous posts, I’ve been talking about how to use snippets in SSMS and how to create your own. There are several types of snippets and one of the special types of snippets that I want to mention are the “surround with” snippets.
If you look at the following block of code:
Imagine that you want to execute the four highlighted lines only when a condition is true. If I hit Ctrl-K and Ctrl-S while they are highlighted, I’m prompted with this:
2025-07-28
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: Development Level: Medium
Question:
You are reviewing T-SQL code and in one query, you find the following:
OPTION (FORCE ORDER)
What is the point of this code, and is it likely to be helpful?
Answer:
FORCE ORDER tells SQL Server to join the tables that are involved in a query, in the order that they are written in the query.
2025-07-27
In an earlier post, I showed how to create a DROP DATABASE template in SSMS. I mentioned that a template wasn’t the best option because a command like this is normally inserted into a script; it’s not the whole script.
That’s where snippets shine. Let’s create a snippet for it.
First let’s open Code Snippets Manager (Tools > Code Snippets Manager):
You’ll see the existing snippet folders. I’ve clicked Add, then created a new folder called GL_Snippets. I created a new folder and pointed to it. For this temporary one, I’ve created it in C:\Temp but you would normally use an appropriate folder.
2025-07-26
Have you ever started to create an object using T-SQL in SQL Server, and thought what’s the right syntax for this?
I’ve worked with SQL Server since 1992 (version 4.2) and yet almost every time I go to create a function, I have to spend a few moments thinking about what the correct syntax is, because there are different types of functions (scalar vs table-valued, inline vs multi-statement).
SSMS has had templates for a long time, and they are useful. In fact, a few days ago, I wrote about how you can create your own.
2025-07-24
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: Security Level: Medium
Question:
You have code in stored procedures that records which users have called the procedures. The stored procedures are defined as:
WITH EXECUTE AS OWNER
You find that when you log the caller of the procedure, you get the owner of the procedure, rather than the caller.
2025-07-23
In another post, I mentioned how useful templates can be. I said that I’d discuss how to create them later. Well, that’s today.
I thought I’d take dropping a database as an example. The supplied template doesn’t work for me, so let’s create a new one.
Note: SQL Server 2016 SP1 introduced DROP DATABASE IF EXISTS but I find that option quite useless. It fails if anyone is connected to the database. And to disconnect people beforehand, you need to first check if it exists, so the statement is pointless.
2025-07-22