Question 1
A financial services company is analyzing VPN logs to track user session durations. The logs contain a user_id, event_type (with values 'login' and 'logout'), and timestamp. The analyst needs to calculate the duration of each session. The following two searches are proposed. Which statement accurately compares them?
Search A:index=vpn sourcetype=vpn_logs | transaction user_id startswith="event_type=login" endswith="event_type=logout" | table user_id, duration
Search B:index=vpn sourcetype=vpn_logs | stats first(_time) as start_time, last(_time) as end_time by user_id | eval duration = end_time - start_time | table user_id, duration
Answer and explanation
Correct answer: B
While both searches can achieve the goal, Search B using stats is far more efficient. The stats command is a streaming command that processes events as they are retrieved and is highly optimized for this type of aggregation. The transaction command is a non-streaming command that must hold all events in memory to group them, making it resource-intensive and much slower, especially with large datasets or long-running transactions.