Oracle 参数 ENABLE_AUTOMATIC_MAINTENANCE_PDB 官方解释，作用，如何配置最优化建议
本站中文解释
ENABLE_AUTOMATIC_MAINTENANCE_PDB参数是用来定义开启操作系统自动恢复非空的PDB实例。当某个PDB实例不可用时，ENABLE_AUTOMATIC_MAINTENANCE_PDB参数可以将其恢复到一次“可用”状态。
要正确设置此参数，应该在服务器上添加ENABLE_AUTOMATIC_MAINTENANCE_PDB参数项，并将该参数值设置为“TRUE”。DBAs通过SQL命令可以设置ENABLE_AUTOMATIC_MAINTENANCE_PDB参数，例如：
ALTER SYSTEM SET ENABLE_AUTOMATIC_MAINTENANCE_PDB=TRUE;
要关闭此参数，可以通过将它的值更改为“FALSE”来完成：
ALTER SYSTEM SET ENABLE_AUTOMATIC_MAINTENANCE_PDB=FALSE;
官方英文解释
ENABLE_AUTOMATIC_MAINTENANCE_PDB can be used to enable or disable the running of automated maintenance tasks for all the PDBs in a CDB or for individual PDBs in a CDB.
| Property | Description |
|---|---|
|
Parameter type |
Boolean |
|
Default value |
|
|
Modifiable |
|
|
Modifiable in a PDB |
Yes |
|
Range of values |
|
|
Basic |
No |
|
Oracle RAC |
The same value should be used for all instances. |
Note:
The value of this parameter in CDB$ROOT (the root of a CDB) has no effect in the root. Automated maintenance tasks are always run in the root, regardless of the setting of this parameter.
By default, the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB is true in CDB$ROOT (the root container in the CDB) and in the individual PDBs in a CDB. This means that by default, automated maintenance tasks are run for the CDB root and all the PDBs in the CDB.
When you change the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB in the CDB root, the new value takes effect in the root and in all the PDBs in the CDB.
Therefore, if you change the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB in the CDB root to false, the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB is also changed to false in all of the PDBs in the CDB.
You can also change the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB in any of the individual PDBs in a CDB, and the value that is set for each individual PDB will be honored. This enables you to enable or disable automated maintenance tasks for individual PDBs.
See Also:
-
“AUTOTASK_MAX_ACTIVE_PDBS” for information about specifying the maximum number of PDBs that can schedule automated maintenance tasks at the same time
-
Oracle Database
Administrator’s Guide for more information about managing automated database maintenance tasks
