Oracle 字典和动态视图
oracle服务显示全部的系统统计信息在v$sysstat 视图中,也用很多视图展现oracle性能和问题快照信息。你能够通过查询这些视图发现
dictionary and dynamic view
Oracle 字典和动态视图
oracle服务显示全部的系统统计信息在v$sysstat 视图中,也用很多视图展现oracle性能和问题快照信息。
你能够通过查询这些视图发现被启动的实例总体信息。
oracle服务在DBA_xxx 视图中显示数据存储统计信息,可以用来查找存储故障(表,簇,索引)
utlbstat and utlestat 工具
你可能需要收集在制定业务时间内的性能特征, 可以用utlbstata.sql 和utlbstat.sql脚本 ,,有经验的人通常用这两个工具去获取数据来调优项目
Oracle 等待事件
如果你正排出数据库系统的故障,那么需要知道有那些等待的进程
oracle 提供了一个等待事件列表,一些字典视图也提供了哪些session 在等待
oracle 诊断和调优包
在调优时可以使用oracle提供的图形界面工具来诊断和调优。例如图形监控、分析、自动调优。
字典和专用视图
在运行分析命令后,字典和专用视图回提供有用的统计信息。例如:
dba_tables dba_tab_columns dba_clusters dba_indexs ,dba_index_stats, index_histogram, dba_histogams.
下面是动态快照和性能试图
v$view v$fixed_table
x$tables
下面分类列出了可用到的一些统计视图
数据库实例信息
v$database
v$instance
v$option
v$parameter
v$backup
v$process
v$waritstat
v$system_event
磁盘信息
v$datafile
v$filestat
v$log
v$log_history
v$dbfile
V$tempfile
v$tempstat
用户和会话信息
v$lock
v$oper_cursor
v$process
v$sort_usage
v$session
v$sessstat
v$transaction
v$session_event
v$session_wait
v$px_sesstat
v$px_session
v$session_object_cache
内存信息
v$buffer_pool_statistics
v$db_object_cache
v$librarycache
v$rowcache
v$systat
v$sgastat
竞争信息
v$lock
v$rollname
v$rollstat
v$waitstat
v$latch
相关阅读:
Oracle物化视图创建报ORA-00942错误解决
Oracle 存储过程刷新物化视图
Oracle物化视图的使用
物化视图实现 Oracle 数据库表双向同步
Oracle物化视图应用笔记

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