Oracle Active Sessions and Wait Events

Lists active user sessions with the running SQL_ID and wait event. Shows the live picture during performance issues.

#v$session#sessions#active#incident

oracle · sql

SELECT s.sid, s.serial#, s.username, s.status, s.machine, s.program,
       s.sql_id, s.event, s.wait_class, s.seconds_in_wait,
       ROUND(s.last_call_et / 60, 1) AS active_minutes
FROM   v$session s
WHERE  s.type = 'USER'
  AND  s.status = 'ACTIVE'
  AND  s.sid <> SYS_CONTEXT('USERENV','SID')
ORDER  BY s.last_call_et DESC;

Operational Notes & Remediation Guidance

High `db file sequential read` indicates single-block index reads; `db file scattered read` indicates full table scans.

Production Safety & Execution Standards

This script is designed for read-only diagnostics; it does not alter schema or modify data directly.
Prior to executing on production systems under high load, verify the target database version (Min. Version: 11g).
Exercise caution with mutating actions (e.g., terminating sessions or dropping indexes) referenced in the notes section.

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