Data Guard备库日志的实时应用与非实时应用

在Dataguard的备库上应用日志的时候，通常有两个语句，但是这两个语句是有区别的，一个是实时应用，一个是非实时应用。 alter database recover managed standby database disconnect from session; alter database recover managed standby database using current logfile disconnect; 测试  --在备库上启用实时应用日志，并创建表 alter database recover managed standby database using current logfile disconnect; --在主库上创建表 19:23:46 SYS@test>create table zbb.t3(id number);   Table created. --在备库上查看表，立刻生效 ZBB@test_stdby>set time on 19:24:02 ZBB@test_stdby>desc t3  Name                                      Null?    Type  ----------------------------------------- -------- ----------------------------  ID                                                 NUMBER   --drop掉表，在备库上启用日志应用，但不是实时的 drop table zbb.t3 purge; alter database recover managed standby database cancel; alter database recover managed standby database disconnect from session; --在主库上创建表 19:26:51 SYS@test>create table zbb.t3 (id number);   Table created.   Elapsed: 00:00:00.03 --在备库上查看创建的表，表不存在 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> --查看是否启用实时应用 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$archive_dest_status where dest_id=2;   RECOVERY_MODE ----------------------- MANAGED REAL TIME APPLY   --关于recover mode的说明 。查询视图V$ARCHIVE_DEST_STATUS