RMAN - backup archivelog all 與 backup database plus archivelog 區別

OLTP系統的生產庫一般都是開啟歸檔模式，當CUD操作頻繁並且時常使用大批次處理時，每天的歸檔日誌也是超級大的，如果長期保留這些歸檔日誌磁碟空間消耗是很恐怖的，所以我們在使用RMAN進行資料庫備份時，將歸檔日誌進行備份，來釋放磁碟空間。<br /> <br /> 1. 備份歸檔日誌方式：<br /> &nbsp; &nbsp;<br /> 1.1. 單獨備份歸檔日誌：backup archivelog all<br /> 1.2 在執行備庫時一起備份歸檔日誌：backup database plus archivelog;<br /> <br /> <br /> 2. 這兩種方式有什麼區別呢？<br /> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;<br /> &nbsp;2.1 執行backup archivelog all &nbsp;命令時執行的步驟：<br /> &nbsp; &nbsp; &nbsp; 1). alter system archive log current; &nbsp; &nbsp; 歸檔當前日誌&nbsp;<br /> &nbsp; &nbsp; &nbsp; 2). backup &nbsp;archivelog all ; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;備份所有歸檔日誌<br /> &nbsp;<br /> &nbsp;2.2 執行backup database plus archivelog，的執行步驟是；<br /> &nbsp; &nbsp; &nbsp; 1).alter system archive log current; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;歸檔當前日誌<br /> &nbsp; &nbsp; &nbsp; 2).backup archivelog all； &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;備份所有歸檔日誌,注意如果備份最佳化被啟用，RMAN只會備份未備份過的日誌<br /> &nbsp; &nbsp; &nbsp; 3).backup database; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 備份資料庫<br /> &nbsp; &nbsp; &nbsp; 4).alter system archive log current; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;歸檔當前日誌<br /> &nbsp; &nbsp; &nbsp; 5).Backs up any remaining archived logs generated during the backup; &nbsp; 備份備份過程中生成的任何剩餘的歸檔日誌&nbsp;<br /> &nbsp;<br /> 3. 刪除歸檔日誌一般在備份歸檔日誌同時加上一個引數：delete all input<br /> &nbsp; &nbsp;例如：backup database plus archivelog delete all input; &nbsp; &nbsp;<br /> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;執行此命令是會將所有的歸檔日誌進行備份，並且在備份的同時刪除已備份的歸檔日誌。<br /> <br /> &nbsp;所以如果在RMAN備份指令碼中有plus archivelog 引數 就無需在備份歸檔日誌之前執行： sql 'alter system archive log current';<br /> <div style="white-space:nowrap;"> <br /> </div>