Kendra Little diagnoses a problem:
Last November, a puzzle was really bothering me. Some queries from an application were timing out frequently after running for 30 seconds, but they were halfway invisible in the SQL Server.
I say “halfway invisible” because I could see the queries while they were running in SQL Server’s dynamic management views using free tools (sp_WhoIsActive and sp_BlitzWho).
But the queries had some odd characteristics:
- They had a sql_handle, but never a query_hash
- They also never showed a plan_hash or execution plan
- I couldn’t find the timeouts in Query Store like a normal timeout
Through the power of communication with other humans (eew, that idea sounds icky), Kendra was able to learn what the problem was and how you can track such issues outside of Query Store.