If a session is ended, the current transaction in that session will be committed and ended. All the database changes made in the current transaction will become permanent. This is called an implicit commit when session is ended. The following tutorial exercise shows you that the "disconnect" command forces the current transaction to be committed and ended. When the session is reconnected, you can see the changes made by the UPDATE statements.

SQL> connect HR/globalguideline

SQL> UPDATE ggl_links SET url = 'globalguideline.COM'

2 WHERE id = 101;

SQL> UPDATE ggl_links SET url = 'globalguideline.COM/html'

2 WHERE id = 110;

SQL> disconnect

SQL> connect HR/globalguideline

SQL> SELECT * FROM ggl_links;

  ID URL   NOTES  COUNTS CREATED

------- ---------------- ---------- ---------- ---------

 101 globalguideline.COM     07-MAY-06

 110 globalguideline.COM/html     07-MAY-06

 112 oracle.com      07-MAY-06

 113 sql.com      07-MAY-06