Identifying Idle User Sessions in Oracle Database

Oracle sessions sorted by logon time

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

Sample Oracle Output:

 1USERNAME             OSUSER          ID              STATUS   LOGIN_TIME     LAST_CALL_ET
 2-------------------- --------------- --------------- -------- -------------- ------------
 3SYS                  oracle          54,58456        ACTIVE   20:09 10/12/23            0
 4SYS                  oracle          52,61761        ACTIVE   21:37 10/12/23          100
 5SYS                  oracle          15,1554         ACTIVE   23:34 09/12/23        79495
 6ORDS_PUBLIC_USER     oracle          286,58632       INACTIVE 23:36 09/12/23        79361
 7ORDS_PUBLIC_USER     oracle          53,20873        INACTIVE 23:36 09/12/23        79360
 95 rows selected.


  • To monitor user session activity by identifying idle sessions and their durations, aiding in resource management and potential troubleshooting.


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, which provides details about active user sessions:
    *   `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.
    *   `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: Calculates idle time in minutes for easy interpretation.
  • Session Status: Provides context about whether sessions are currently active or inactive.
  • User-Oriented 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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