SQL Interview: 57 Query Stuck

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?

Answer:

Generally, when queries appear stuck, it’s because they are being blocked by another process. Look for processes that are blocking it.

You can see that in Activity Monitor and/or by querying sys.dm_exec_requests.

2025-06-21