What does session mean in oracle?

A session in Oracle is a temporary connection to the database server for users to perform queries and operations. Each session has a unique SID. A session consists of connection information, environment information, transaction status, lock information and performance statistics. It is allocated from the session pool when a session is created and reused when the session is closed. To view session information, you can query the v$session and V$SESSION_LONGOPS views.

Session in Oracle

In the Oracle database, a session is a session established with the database server. Temporary connection. It is the medium through which users interact with the database, allowing users to perform queries, update data, and perform other operations. Each session has a unique session identifier (SID) that distinguishes it from other sessions.

Components of the session:

• Connection information: Connection parameters used when establishing the session, such as username, password and connection string.
• Environment information: The current settings for the session, such as time zone, locale, and session variables.
• Transaction status: Whether the session is currently in a transaction, and the status of the transaction (committed, rolled back).
• Lock information: Any locks held by the session and the lock type and status.
• Performance statistics: Performance information associated with the session, such as query execution time and memory usage.

Session life cycle:

• Creation: When a user connects to the database, a session is created.
• Usage: Sessions are used to perform queries and operations.
• Close: The session is closed when the user disconnects or the session idle times out.

Session Management:

Oracle Database Management System (DBMS) maintains a session pool that contains a list of available sessions. When a user connects to the database, the DBMS allocates a session from the session pool. To optimize performance, the DBMS also automatically closes idle sessions and reuses them.

View session information:

You can view information about the session, such as SID, username, and connection time, by querying the v$session view. You can also use the V$SESSION_LONGOPS view to view long-running operations.

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