使数据库为归档模式

1。若数据库为非归档模式，则数据不能保持它的完整。1。su - Oracle

1.1. modify the /opt/oracle/admin/dbora817/pfile/initdbora817.ora,make sure that

    log_archive_start = true

    log_archive_dest_1 = "location=/opt/oracle/admin/dbora817/arch"

    log_archive_format = arch_%t_%s.arc

   are not commented.

2. sqlplus '/ as sysdba'

3. SQL>shutdown

   SQL>startup mount

   SQL>alter database archivelog;

   SQL>alter database open;

4. verify:

   SQL>archive log list

Database log mode              Archive Mode

Automatic archival             ENABLED

Archive destination            /opt/oracle/admin/dbora817/arch

Oldest online log sequence     19

Next log sequence to archive   21

Current log sequence           21