standby db log sequence gap

From: <dba.orcl_at_gmail.com>
Date: 1 May 2005 19:43:32 -0700
Message-ID: <1115001812.112941.192170@o13g2000cwo.googlegroups.com>

Hi:

I am not very familiar with standby database. So kindly help me to understand why there is a huge gap between "Oldest online log sequence" and "Current log sequence" in standby db (which is not the case in primary).
Note:- the standby db is operating in recovery mode for the last 2 Hrs.

Primary

---

SQL> archive log list

Database log mode              Archive Mode
Automatic archival             Enabled

Archive destination
Z:\oracle\product\10.1.0\db_1\database\archive\primary Oldest online log sequence 87
Next log sequence to archive 89
Current log sequence 89
SQL> Physical Standby

---

SQL> archive log list

Database log mode              Archive Mode
Automatic archival             Enabled

Archive destination
Z:\oracle\product\10.1.0\db_1\database\archive\standby Oldest online log sequence 72
Next log sequence to archive 0
Current log sequence 89
SQL> When I issue a query in standby DB, it says till sequence#88 has been applied.

SQL> SELECT SEQUENCE#,APPLIED FROM V$ARCHIVED_LOG order by sequence#;
:
:

 SEQUENCE# APP
---------- ---

        71 YES
        72 YES
        73 YES
        74 YES
        75 YES
        76 YES
        77 YES
        78 YES
        79 YES
        80 YES
        81 YES
        82 YES
        83 YES
        84 YES
        85 YES
        86 YES
        87 YES
        88 YES

Received on Sun May 01 2005 - 21:43:32 CDT