SQL> desc v$log;
Name Null? Type
----------------------------------------- -------- ----------------------------
GROUP# NUMBER
THREAD# NUMBER
SEQUENCE# NUMBER
BYTES NUMBER
BLOCKSIZE NUMBER
MEMBERS NUMBER
ARCHIVED VARCHAR2(3)
STATUS VARCHAR2(16)
FIRST_CHANGE# NUMBER
FIRST_TIME DATE
NEXT_CHANGE# NUMBER
NEXT_TIME DATE
SQL> desc v$logfile;
Name Null? Type
----------------------------------------- -------- ----------------------------
GROUP# NUMBER
STATUS VARCHAR2(7)
TYPE VARCHAR2(7)
MEMBER VARCHAR2(513)
IS_RECOVERY_DEST_FILE VARCHAR2(3)
SQL> select GROUP#,BYTES/1024/1024M,MEMBERS from v$log;
GROUP# M MEMBERS
---------- ---------- ----------
1 50 2
2 50 2
3 50 2
SQL> select GROUP#,MEMBER from v$logfile;
GROUP#
----------
MEMBER
--------------------------------------------------------------------------------
3
/u01/app/oracle/oradata/VDEDU/redo03.log
2
/u01/app/oracle/oradata/VDEDU/redo02.log
1
/u01/app/oracle/oradata/VDEDU/redo01.log
GROUP#
----------
MEMBER
--------------------------------------------------------------------------------
1
/u01/app/oracle/oradata/VDEDU/redo04.log
2
/u01/app/oracle/oradata/VDEDU/redo05.log
3
/u01/app/oracle/oradata/VDEDU/redo06.log
6 rows selected.
SQL> set lines 1000
SQL> /
GROUP# MEMBER
---------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3 /u01/app/oracle/oradata/VDEDU/redo03.log
2 /u01/app/oracle/oradata/VDEDU/redo02.log
1 /u01/app/oracle/oradata/VDEDU/redo01.log
1 /u01/app/oracle/oradata/VDEDU/redo04.log
2 /u01/app/oracle/oradata/VDEDU/redo05.log
3 /u01/app/oracle/oradata/VDEDU/redo06.log
6 rows selected.
alter database add logfile member '/u01/app/oracle/oradata/VDEDU/redo03_II.log' to group 3;
Database altered.
SQL> select GROUP#,BYTES/1024/1024M,MEMBERS from v$log
2 ;
GROUP# M MEMBERS
---------- ---------- ----------
1 50 2
2 50 2
3 50 4
SQL> select GROUP#,MEMBER from v$logfile;
GROUP# MEMBER
---------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3 /u01/app/oracle/oradata/VDEDU/redo03.log
2 /u01/app/oracle/oradata/VDEDU/redo02.log
1 /u01/app/oracle/oradata/VDEDU/redo01.log
1 /u01/app/oracle/oradata/VDEDU/redo04.log
2 /u01/app/oracle/oradata/VDEDU/redo05.log
3 /u01/app/oracle/oradata/VDEDU/redo06.log
3 /u01/app/oracle/oradata/VDEDU/redo07.log
3 /u01/app/oracle/oradata/VDEDU/redo03_II.log
8 rows selected.
SQL> select GROUP#,MEMBER FROM v$logfile order by 1;
GROUP# MEMBER
---------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 /u01/app/oracle/oradata/VDEDU/redo04.log
1 /u01/app/oracle/oradata/VDEDU/redo01.log
2 /u01/app/oracle/oradata/VDEDU/redo05.log
2 /u01/app/oracle/oradata/VDEDU/redo02.log
3 /u01/app/oracle/oradata/VDEDU/redo07.log
3 /u01/app/oracle/oradata/VDEDU/redo03_II.log
3 /u01/app/oracle/oradata/VDEDU/redo06.log
3 /u01/app/oracle/oradata/VDEDU/redo03.log
8 rows selected.
SQL> alter system switch logfile;
System altered
SQL> alter database drop logfile member '/u01/app/oracle/oradata/VDEDU/redo03_II.log';
Database altered.