创建序列：

SQL> create sequence dept_seq

minvalue 60

maxvalue 10000

start with 60

increment by 10;

2.RMAN删除备份：

删除备份（保留最近1天备份的情况下，删除其他备份）：

RMAN> delete noprompt obsolete recovery window of 1 days;

RMAN> delete noprompt backup; 删除所有的备份文件

3.rman 备份表空间：

run{

allocate channel t1 type disk;

backup

tablespace AGILE

format '/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bk0_%s_%p_%t';

release channel t1;

}

4.rman 双备份(副本数为2)：

rman备份一个数据文件：

run{

allocate channel t1 type disk;

set backup copies=2;

backup

datafile '/u01/app/oradata/HAITIAN/itil1.dbf'

format '/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bk_%s_%p_%t','/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bkdatafile_%U';

release channel t1;

}

5.rman 双备份(副本数为2)：

run{

allocate channel t1 type disk;

set backup copies=2;

backup

datafile '/u01/app/oradata/HAITIAN/itil1.dbf'

format '/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bkdatafile_%U','/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bkdatafile_%U';

release channel t1;

}

6.rman 备份归档日志文件：

run{

allocate channel t1 type disk;

backup

archivelog all

format '/u01/app/flash_recovery_area/HAITIAN/backupset/2019_12_17/bkdatafile_%U';

release channel t1;

}

7.修改初始化参数max_enabled_roles导致DB无法启动故障解决：

[故障原因]：

SQL>alter system set max_enabled_roles=124 scope=spfile;

修改了初始化参数max_enabled_roles。

[故障现象]：

SQL> startup mount;

ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance

ORA-32004: 为 RDBMS 实例指定了废弃或过时的参数

[故障分析]：

解决方法：

1.show parameter user_dump_dest;

2.cd /u01/app/diag/rdbms/haitian/HAITIAN/trace/

3.查看alter的日志alert_HAITIAN.log：

发现具体参数错误：

Deprecated system parameters with specified values:

max_enabled_roles

[故障解决]：

1.SQL> shutdown immediate;

2.SQL> startup;

会出现：ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance

3.alter system reset max_enabled_roles scope=spfile sid='*';

4.SQL> shutdown immediate;

5.SQL> startup;