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Oracle中的Parallel Execution 和有用的view

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Jun 07, 2016 pm 05:17 PM

Oracle中的Parallel Execution 和有用的view，默认是parallel_max_servers是大于0的也就是打开的alter session enable parallel

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Oracle中的Parallel Execution 和有用的view

[日期：2012-08-04] 来源：Linux社区作者：icybay [字体：]

默认是parallel_max_servers是大于0的也就是打开的

alter session enable parallel [ddl | dml | query];
alter session disable parallel [ddl | dml | query];
alter session force parallel ddl parallel 5;

用来分析DB性能的几个view.

V$PROCESS
Contains information about the currently active processes

V$SESSION
Lists session information for each current session

V$SESS_IO
Contains I/O statistics for each user session

V$SESSION_LONGOPS
Displays the status of various operations that run for longer than 6 seconds (in absolute time). These operations currently include many backup and recovery functions, statistics gathering, and query execution. More operations are added for every Oracle Database release.

V$SESSION_WAIT
Displays the current or last wait for each session

V$SESSION_WAIT_HISTORY
Lists the last ten wait events for each active session

V$WAIT_CHAINS
Displays information about blocked sessions

V$SYSSTAT
Contains session statistics

V$RESOURCE_LIMIT
Provides information about current and maximum global resource utilization for some system resources

V$SQLAREA
Contains statistics about shared SQL areas. Contains one row for each SQL string. Provides statistics about SQL statements that are in memory, parsed, and ready for execution

更多Oracle相关信息见Oracle 专题页面 ?tid=12

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