dataguard的啟動和應用歸檔日誌的語句

alter database recover managed standby database disconnect from session;

--應用備庫的歸檔日誌

 

alter database recover managed standby database using current logfile disconnect from session;

--應用備庫的standby redo日誌，關機的時候不會歸檔，重啟後例項恢復redo日誌會進入資料庫

 

以上兩種方式的切換可以透過alter database recover managed standby database cancel來實現

驗證：主庫備庫執行select open_mode,protection_mode,protection_level from v$database檢視結果

      備庫執行SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME, APPLIED FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#;檢視archive log的applied是否yes

 

DATAGURAD直接startup後，create/alter user和create table都報錯如下，alter system是可以的，畢竟是修改引數

ORA-16000: database open for read-only access

 

 

一般啟動的步驟如下

startup  nomount;

alter database mount standby database;

alter database open read only;

alter database recover managed standby database disconnect from session;

alter database recover managed standby database cancel;

alter database recover managed standby database disconnect from session;

 

其實可以直接如下(也是最好的一種，畢竟遇到很多歸檔需要recover時是不能直接open的)

startup mount（預設就是standby database了，因為是restore主庫的standby controlfile）

alter database open read only;

alter database recover managed standby database disconnect from session;

alter database recover managed standby database cancel;

alter database recover managed standby database disconnect from session;

 

 

其實更可以直接如下

Startup(備庫startup後預設就是read only，可以查詢select open_mode from v$database，遇到很多歸檔日誌需要recover的時候時會報錯需要更多的恢復然後提示只能到mount狀態)

alter database recover managed standby database disconnect from session;

alter database recover managed standby database cancel;

alter database recover managed standby database disconnect from session;