Our software systems can sometimes give us unexpected values, and SQL Server is no exception. One of my colleagues recently encountered a strange issue with the @@ServerName property in SQL Server. This property is used to retrieve the name of the local server that SQL Server is running on. However, in his case, the value returned by @@ServerName was NULL.

As a best practice, whenever an error occurs on a server, it is common to ask for the @@Version to gather information about the installed version, service pack, and cumulative updates. This information is crucial for troubleshooting and diagnosing issues. However, my colleague’s experience with a NULL @@ServerName value got me curious, and I wanted to investigate further.

After some research and discussions with my SQL buddies, I discovered that the @@ServerName property is set during installation. However, there are instances where it may be NULL or incorrect. To verify the current value of @@ServerName, you can run the following T-SQL query:

SELECT @@SERVERNAME;

If the @@ServerName property is NULL, you can fix the issue by running the following command:

EXEC sp_addserver '<LocalServerName>', local;

However, please note that fixing this issue requires restarting the SQL Server instance, which will result in an outage.

If the @@ServerName property is incorrect, you can correct it by running the following commands:

EXEC sp_dropserver 'old_name';
EXEC sp_addserver 'new_name', 'local';

Although the solution to this problem is relatively simple, it is still intriguing to understand why this behavior occurs. If you have encountered this issue on your server, I would love to hear about your experience and how you resolved it. Understanding the cause of this issue can help us prevent it in the future.

Thank you for reading and happy SQL Server troubleshooting!