Oracle 重做日志調整 SQL語句

Oracle 資料庫安裝之後，重做日志預設為 3組，如果需要新增删除，可以通過以下方式！

查詢：

set line222
col member for a60
select a.group#,b.member member,a.bytes/1024/1024 "size(M)" from v$log a,v$logfile b where a.group#=b.group#;
           

新增：

單機資料庫：

alter database add logfile group 4 '/oradata/orcl/redo04.log' size 50M;
alter database add logfile group 5 '/oradata/orcl/redo05.log' size 50M;
alter database add logfile group 16 '/oradata/orcl/redo16.log' size 1024M;
alter database add logfile group 17 '/oradata/orcl/redo17.log' size 1024M;
alter database add logfile group 18 '/oradata/orcl/redo18.log' size 1024M;
           

RAC叢集資料庫：

alter database add logfile thread 1 
group 4 '/oradata/orcl/redo04.log' size 50M,
group 5 '/oradata/orcl/redo05.log' size 50M,
group 6 '/oradata/orcl/redo06.log' size 50M;

alter database add logfile thread 2
group 7 '/oradata/orcl/redo07.log' size 50M,
group 8 '/oradata/orcl/redo08.log' size 50M,
group 9 '/oradata/orcl/redo09.log' size 50M;
           

删除：

alter database drop logfile group 16; 
alter database drop logfile group 17; 
alter database drop logfile group 18; 
           

???? 注意：如果目前要删除的 logfile 狀态不是

INACTIVE

，那麼删除會報錯，需要執行

ALTER SYSTEM SWITCH LOGFILE;

來切換日志，直到狀态為

INACTIVE

才可以删除！