Your events have a user and a time but no visit ID. Here is how to infer sessions from an idle gap with LAG and a running sum.
What is Source_Database_ID in Sys.Databases?- Interview Question of the Week #232
Question: What is Source_Database_ID in Sys.Databases and why it is mostly NULL? Very interesting question, I received indeed.
sysxmitqueue in msdb: Why It Grows and How to Clear It
Sysxmitqueue in msdb fills up when Service Broker messages cannot leave the server. A tested demo in its own database shows the pile, the reason, a one conversation cleanup and the NEW_BROKER reset. The msdb steps follow the same order.
Profiling a Table’s Data: Nulls, Distinct Values and Lengths
Start profiling a table’s data with null counts, distinct values, lengths, and generated checks that expose misleading column definitions.
Trivial Plan: Why Some Queries Skip Full Optimization
Identify a trivial plan in SSMS and cached XML, understand skipped optimizer work, and compare a more complex query without forcing it.





