Oracle 视图 V$ROWCACHE_PARENT 官方解释，作用，如何使用详细说明
本站中文解释
Oracle视图V$ROWCACHE_PARENT是Oracle数据库11gR2版本提供的数据字典视图，其收集到当前正在使用System Global Area (SGA)中的Row Cache的信息。 V$ROWCACHE_PARENT视图在Oracle数据库中用于管理和维护SGA中的行缓存。行缓存提供当前的词汇直观的信息，如列的名称、缓存内容的特性等，可用于检测操作系统在查询处理时的数据内存情况。
要查看SGA中Row Cache的信息，可使用下面的SQL语句：
SELECT *
FROM V$ROWCACHE_PARENT;
该语句将会列出与行缓存映射的相关信息，包括每一行缓存的描述、打开次数、列名、类型及保留比例等。
官方英文解释
V$ROWCACHE_PARENT displays information for parent objects in the data dictionary. There is one row per lock owner, and one waiter for each object. This row shows the mode held or requested. For objects with no owners or waiters, a single row is displayed.
| Column | Datatype | Description |
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Index of the row |
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Hash value |
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Address of the parent object |
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Parent cache ID |
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Parent cache name |
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Indicates whether the object is an existing object |
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Mode the lock is held in |
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Mode the lock is requested in |
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Transaction currently locking the object |
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Address of the session |
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Mode in which instance lock is being requested. This column is only relevant for Real Application Clusters. |
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Whether the instance lock needs to be released. This column is only relevant for Real Application Clusters. |
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Type of instance lock. This column is only relevant for Real Application Clusters. |
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ID associated with the instance lock. This column is only relevant for Real Application Clusters. |
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ID associated with the instance lock. This column is only relevant for Real Application Clusters. |
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Contents of the key. This column is only relevant for Real Application Clusters. |
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The ID of the container to which the data pertains. Possible values include:
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