Tracking Idle Time for User Sessions in Oracle Database

Display all Oracle users by the time since last user activity



SQL Code

1set lines 100 pages 999
2select username
3,      floor(last_call_et / 60) "Minutes"
4,      status
5from   v$session
6where  username is not null
7order by last_call_et
8/

Sample Oracle Output:

 1USERNAME                Minutes STATUS
 2-------------------- ---------- --------
 3SYS                           0 ACTIVE
 4SYS                           1 ACTIVE
 5ORDS_PUBLIC_USER           1305 INACTIVE
 6ORDS_PUBLIC_USER           1305 INACTIVE
 7SYS                        1307 ACTIVE
 8
 95 rows selected.
10SQL>

Purpose:

  • To monitor user session activity, specifically focusing on idle sessions and their durations, aiding in resource management and potential troubleshooting.

Breakdown:

Formatting Output:

*   `set lines 100 pages 999`: Adjusts display settings to accommodate potentially lengthy results.

Querying Session Data:

*   `select username, floor(last_call_et / 60) "Minutes", status from v$session`: Retrieves specific information from the `v$session` view:
    
    *   `username`: Identifies the user associated with each session.
    *   `floor(last_call_et / 60) "Minutes"`: Calculates the approximate duration of inactivity in minutes since the last call from each session, making idle time easily interpretable.
    *   `status`: Indicates the current status of each session (e.g., ACTIVE, INACTIVE).
    
*   `where username is not null`: Filters results to include only sessions with known usernames, excluding system-level sessions.
*   `order by last_call_et`: Presents results in ascending order of idle time, highlighting the longest-idle sessions first.

Key Points:

  • Idle Session Focus: Targets sessions that haven't made database calls recently, potentially indicating inactive users or processes.
  • Inactivity Duration in Minutes: Calculates idle time in minutes for easy interpretation and prioritization.
  • Session Status Context: Provides information about whether sessions are currently active or inactive, aiding in understanding their state.
  • User-Centric View: Presents information in a user-friendly format, aiding in understanding session activity patterns.

Insights and Explanations:

  • Resource Management: Identifying idle sessions can help optimize resource usage by potentially terminating or reducing resources for inactive sessions.

  • Troubleshooting:

    • Long-idle sessions might indicate issues such as hung processes or users forgetting to log out.
    • Analyzing idle sessions can help identify potential problems and take corrective actions.
  • Monitoring:

    • Regularly monitoring idle sessions can help proactively manage database resources and prevent performance issues.
  • Customization:

    • The code can be modified to adjust idle time thresholds for defining "idle" sessions or to filter for specific users or session statuses based on analysis needs.

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