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: Administrator Level: Medium
Question:
You are considering adding an index to a table.
You have heard that adding indexes slows down UPDATE commands.
Does adding an index always slow down updates? If so, why? If not, why not?
2025-05-20
If you are working with databases with large numbers of objects, the contents of Object Explorer in SQL Server Management Studio can start to become a bit overwhelming. I wish it offered an option to group by schema. That would be helpful.
But you can at least filter by things like schema, when you need to work with a specific set of objects. You’ll notice that if you click on the database name, that the filter in the toolbar is grayed out, but if you click on a node below that like Tables, you can click on the toolbar filter icon. You can also right-click the node and choose to filter:
2025-05-19
I’ve recently been reading a few articles and discussions around linked servers, and I’ve noticed two things:
I do think they’re pretty easy to configure, but they’re also easy to configure badly.
And that leads us to the main cause of the second issue: performance.
I review the configuration of a lot of systems, and the primary issue I see with how linked servers are configured, is that the Server Option Collation Compatible has been left at the default value.
2025-05-18
I started working with SQL Server in 1992, but all through the 1980’s and 1990’s, I was also working with Progress 4GL. I thought it was the best of the character-based 4GLs but unfortunately, they did a poor job of migrating to Windows and we decided to stop using the product.
One thing that I used to love with Progress though is that the metadata for each column in the database was much richer than what is present in SQL Server. In fact, Microsoft Access was probably closer to it in that regard. It’s something I really missed when moving to SQL Server. In Progress, when I defined a column, I could also define things like:
2025-05-17
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: Administrator Level: Medium
Question:
Your database application has been suffering from signficant blocking issues.
One developer has suggested enabling RCSI for the database.
If you do that, what’s different about how the database would operate?
What code changes are needed to use it?
2025-05-16
I’ve mentioned in an earlier article about scripting multiple objects at once, how useful the Object Explorer Details window is, and how little understood it is.
Another useful option in it, is that the displayed columns can be changed. In particular, you can add columns that would be useful. Let’s look at an example.
In Object Explorer, I’ve expanded the WideWorldImporters database and clicked on the word Tables:
Next, I hit the F7 key, and the Object Explorer Details pane opens showing this:
2025-05-13
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: Developer Level: Intro
Question:
You need to extract the hour component from a datetime value.
Which function should you use?
Answer:
To do this in SQL Server, you should use the DATEPART function.
2025-05-12
If you want to script all the indexes on a table (or all the tables, all the stored procedures, etc, etc.), you can do that the long way by using the Generate Scripts right-click option for a database, but there’s a better way.
Let’s use the Purchasing.PurchaseOrderLines table from WideWorldImporters as an example. Here are the indexes on it:
The scripting options are well-known. You right-click the object, and can navigate to the scripting option:
2025-05-11
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: Developer Level: Intro
Question:
You have a table named HumanResources.Employees. Some employees are managers.
You want to join the table to itself to join employee rows with their manager rows.
What is required when you join a table to itself, that is not required for joining separate tables?
2025-05-10
Previously I showed how useful it is to be able to drag columns from either a table or from user-defined table type onto a query window.
But one of the first comments I hear from people who did that is:
I hate all those square brackets. How do I stop that?
The option to do that was added to Tools> Options > SQL Server Object Explorer > Commands:
Bonus points for the team because they also provided us with an option to decide whether schema names are dragged as well. That’s mostly used for tables but also applies to other schema-bound objects like stored procedures.
2025-05-09
