Oracle 视图 V$RESULT_CACHE_STATISTICS 官方解释,作用,如何使用详细说明

本站中文解释

Oracle视图V$RESULT_CACHE_STATISTICS以V$通用视图接口的形式提供的, 用于查询被保存在结果缓存中的查询语句和应用程序的状态。结果缓存是一种基于查询语句的缓存技术, 其中由表、视图、存储过程等查询构成的查询语句的结果被保存起来,避免再次执行该查询以获取相同的结果。

可以使用V$RESULT_CACHE_STATISTICS 视图来检索由被保存在结果缓存中的查询语句和应用程序提交的状态信息,例如服务名、类型、查询统计数据(例如此查询由几个客户端DB提交)可用空间、缓存结果个数、保存时间、访问次数等等。

要使用V$RESULT_CACHE_STATISTICS 视图,应指定要检索的被缓存的查询结果的信息,如查找某个客户端的针对某种查询的状态、类型或者查询统计数据,以及要排序检索结果的顺序。

官方英文解释

V$RESULT_CACHE_STATISTICS displays various result cache settings and usage statistics.

Column Datatype Description

ID

NUMBER

Statistic number

NAME

VARCHAR2(128)

Name of the statistic (see Table 9-6)

VALUE

VARCHAR2(81)

Value of the statistic

CON_ID

NUMBER

The ID of the container to which the data pertains. Possible values include:

  • 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

  • 1: This value is used for rows containing data that pertain to only the root

  • n: Where n is the applicable container ID for the rows containing data

Table 9-6 V$RESULT_CACHE_STATISTICS and V$RESULT_SUBCACHE_STATISTICS Statistics

Statistic Name Description

Block Count Current

Number of memory blocks currently allocated

Block Count Maximum

Maximum number of memory blocks allowed

Block Size (Bytes)

Size of each memory block

Create Count Failure

Number of cache results that failed to create

Create Count Success

Number of cache results successfully created

Delete Count Invalid

Number of invalid cached results deleted

Delete Count Valid

Number of valid cached results deleted

Find Copy Count

Number of results copied directly out of the cache

Find Count

Number of cached results that were successfully found

Global Load Rate

Rate at which cached results were fetched from remote instances (in bytes per 10 milliseconds)

Global Prune By Self Count

Number of times this instance did not provide a cached result to a remote instance because this instance deemed it inefficient to do so

Global Prune Count

Number of times this instance did not fetch a cached result from a remote instance because it was deemed inefficient to do so

Hash Chain Length

Average length of items in the hash chain

Invalidation Count

Total number of invalidations

Result Size Maximum (Blocks)

Maximum number of blocks allowed for a single result

Subcache Count

Number of subcaches in the result cache

See Also:

“V$RESULT_SUBCACHE_STATISTICS”


数据运维技术 » Oracle 视图 V$RESULT_CACHE_STATISTICS 官方解释,作用,如何使用详细说明