在Dataguard的備庫上應(yīng)用日志的時候，通常有兩個語句，但是這兩個語句是有區(qū)別的，一個是實時應(yīng)用，一個是非實時應(yīng)用。

alter database recover managed standby database disconnect from session;（非實時應(yīng)用）
alter database recover managed standby database using current logfile disconnect;（實時應(yīng)用）


測試

--在備庫上啟用實時應(yīng)用日志，并創(chuàng)建表

alter database recover managed standby database using current logfile disconnect;
19:23:46 SYS@test>create table zbb.t3(id number);

Table created.

Elapsed: 00:00:00.03
19:23:59 SYS@test>
--在備庫上查看表，立刻生效

ZBB@test_stdby>set time on
19:24:02 ZBB@test_stdby>desc t3
Name? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ???Null?? ? Type
----------------------------------------- -------- ----------------------------
ID? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ? NUMBER

19:24:04 ZBB@test_stdby>
--drop掉表，在備庫上啟用日志應(yīng)用，但不是實時的

drop table zbb.t3 purge;
alter database recover managed standby database cancel;
alter database recover managed standby database disconnect from session;
--在主庫上創(chuàng)建表

19:26:51 SYS@test>create table zbb.t3 (id number);

Table created.

Elapsed: 00:00:00.03
--在備庫上查看創(chuàng)建的表，表不存在

19:28:35 SYS@test>
19:28:38 ZBB@test_stdby>desc zbb.t3
ERROR:
ORA-04043: object zbb.t3 does not exist


19:28:41 ZBB@test_stdby>

19:30:04 ZBB@test_stdby>desc zbb.t3
ERROR:
ORA-04043: object zbb.t3 does not exist


19:30:08 ZBB@test_stdby>
--查看是否啟用實時應(yīng)用

select recovery_mode from v$archive_dest_status where dest_id=2;
19:28:35 SYS@test>select recovery_mode from v$archive_dest_status where dest_id=2;

RECOVERY_MODE
-----------------------
MANAGED

Elapsed: 00:00:00.01
19:31:34 SYS@test>

SYS@test>select recovery_mode from v$archive_dest_status where dest_id=2;

RECOVERY_MODE
-----------------------
MANAGED REAL TIME APPLY

SYS@test>