OCP-052

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51.

1> SEC_PROTOCOL_ERROR_FURTHER_ACTION specifies the further execution of a server process when receiving bad packets from a possibly malicious client.

2> SEC_PROTOCOL_ERROR_FURTHER_ACTION = { CONTINUE | (DELAY,integer) | (DROP,integer) }

3> (DROP,integer)

The server forcefully terminates the client connection after integer cumulative bad packets. The server protects itself at the expense of the client (for example, a client transaction may be lost). The client may reconnect and attempt the same operation.

52. 

1> DB_SECUREFILE specifies whether or not to treat LOB files as SecureFiles.DB_SECUREFILE = { NEVER | PERMITTED | ALWAYS | IGNORE }

2> DB_ULTRA_SAFE sets the default values for other parameters that control protection levels.DB_ULTRA_SAFE = { OFF | DATA_ONLY | DATA_AND_INDEX },

• DATA_ONLY

  • DB_BLOCK_CHECKING will be set to MEDIUM.

  • DB_LOST_WRITE_PROTECT will be set to TYPICAL.

  • DB_BLOCK_CHECKSUM will be set to FULL.

58. Baseline Templates

You can also create baselines for a contiguous time period in the future using baseline templates. There are two types of baseline templates: single and repeating.

You can use a single baseline template to create a baseline for a single contiguous time period in the future. This technique is useful if you know beforehand of a time period that you intend to capture in the future. For example, you may want to capture the AWR data during a system test that is scheduled for the upcoming weekend. In this case, you can create a single baseline template to automatically capture the time period when the test occurs.

You can use a repeating baseline template to create and drop baselines based on a repeating time schedule. This is useful if you want Oracle Database to automatically capture a contiguous time period on an ongoing basis. For example, you may want to capture the AWR data during every Monday morning for a month. In this case, you can create a repeating baseline template to automatically create baselines on a repeating schedule for every Monday, and automatically remove older baselines after a specified expiration interval, such as one month.

66. 手动管理SGA的参数如下：SHARED_POOL_SIZE,DB_CACHE_SIZE,LARGE_POOL_SIZE,STREAMS_POOL_SIZE,JAVA_POOL_SIZE。要启用     SGA自动管理，则需要将上述参数设置为0，并设置SGA_TARGET来启用自动共享内存管理（automatic shared memory management，ASSM）

125. CHANGE FAILURE in RMAN,enables you to change priority or close failures recorded in the Automatic Diagnostic Repository.

140. Health Monitor是一组检查，会在特定错误条件出现时自动运行，也可以根据DBA的指示以手动方式运行。检查结果不存储在数据库，而存储在文件系统 中。其原因在于，一些错误的性质决定了数据库不再可用：因此，需要一个外部知识库来存储Health Monitor的结果。该知识库就是ADR。

       只能在不同阶段运行不同的Health Monitor检查：

       在nomount阶段，仅运行“DB Structure Integrity”检查，而且它只检查控制文件的完成性。

       在mount阶段，“DB Structure Integrity”检查将检查控制文件、联机重做日志文件和数据文件头的完整性，还可运行“Redo Integrity Check”，以检查联机和归档日志文件的可访问性及其是否受损。

       在open阶段，可能运行扫描每个数据块是否受损的检查，并检查数据字典和撤销段的完整性。 

198. RMAN supports two basic types of duplication: active database duplication and backup-based duplication