Sql-Interview

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:

Public key encryption is based on combinations of private keys and public keys.

When you install a certificate on a SQL Server, to be used for client connection encryption, which key or keys are contained in the certificate?

2025-07-15

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: Intro

Question:

You have a table of transactions. You need to select all the transactions for a particular date, based on the TransactionDateTime column. It holds datetime data type value. The date is stored in the @RequiredDate variable.

2025-07-11

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: Administration Level: Medium

Question:

You are reviewing database settings for a server.

You notice that one database has AUTO_CLOSE configured. Your model database does not have it enabled.

What is the most likely cause for that setting to be enabled, and what effect does enabling it have?

2025-07-07

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 from an application.

You notice in the definition of some tables, the timestamp data type has been used. In other tables, the rowversion data type has been used for similar purposes.

2025-07-03

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: Advanced

Question:

You are reviewing T-SQL code from an application.

You notice that a view includes WITH SCHEMA_BINDING in its declaration.

What does that affect?

Answer:

Adding WITH SCHEMA_BINDING to a view definition ensures that the underlying objects (like tables) cannot be changed while the view exists.

2025-06-29

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:

If a SQL Server table has six triggers associated with it, what control do you have over the order that the triggers fire in?

Answer:

SQL Server doesn’t provide an option to control trigger firing order. However, it does provide an option to choose the first trigger to fire, and the last trigger to fire.

2025-06-25

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:

The CPU of a SQL Server is at 2%. Very little I/O is happening.

A query has been running for a long time, and seems stuck i.e., doesn’t seem to be doing anything, what’s likely to be the issue?

2025-06-21

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: Intro

Question:

You are writing Azure SQL Database code that needs to concatenate strings.

You have previously used the + operator to do this.

Which other operator can be used for concatenating strings?

Answer:

Azure SQL Database supports the double-pipe || operator for string concatenation.

2025-06-17

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: Administration Level: Medium

Question:

You have code that uses transactions.

There is an outer transaction that contains an inner transaction.

If the inner transaction code executes a ROLLBACK, what is rolled back? Is it the inner transaction, the outer transaction, or both?

2025-06-13

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: Administrtaion Level: Advanced

Question:

You have deployed a database application into production.

Soon after, you get reports that large numbers of deadlocks are occurring.

What is the most important first step in resolving deadlocks?

Answer:

While it might appear that looking into locking processes, etc. is critical, it is pointless reviewing these until you are certain that queries on the system are running efficiently.

2025-06-09