DirectPathReads

Oracle Database SQL Tuning Guide---8 Optimizer Access Paths    

Direct Path Reads
In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.
The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.

Situations in which Oracle Database may perform direct path reads include:

成都创新互联公司长期为近1000家客户提供的网站建设服务,团队从业经验10年,关注不同地域、不同群体,并针对不同对象提供差异化的产品和服务;打造开放共赢平台,与合作伙伴共同营造健康的互联网生态环境。为勐海企业提供专业的做网站、网站建设勐海网站改版等技术服务。拥有十年丰富建站经验和众多成功案例,为您定制开发。

  • Execution of a CREATE TABLE AS SELECT statement

  • Execution of an ALTER REBUILD or ALTER MOVE statement

  • Reads from a temporary tablespace

  • Parallel queries

  • Reads from a LOB segment




 
Direct Path Reads

In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.

The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.

Direct Path Reads

In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.

The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.

Direct Path Reads

In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.

The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.

Direct Path Reads

In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.

The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.

Direct Path Reads
In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.


The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.
Direct Path Reads
In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.


The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.












新闻标题:DirectPathReads
新闻来源:http://hxwzsj.com/article/poiioc.html

其他资讯

Copyright © 2025 青羊区翔捷宏鑫字牌设计制作工作室(个体工商户) All Rights Reserved 蜀ICP备2025123194号-14
友情链接: app网站建设 公司网站建设 网站设计 网站建设公司 成都网站建设 高端品牌网站建设 成都品牌网站设计 网站制作公司 重庆电商网站建设 网站建设公司 盐亭网站设计 营销网站建设 成都企业网站建设 定制网站建设 外贸营销网站建设 响应式网站设计 成都网站设计 成都网站建设公司 重庆企业网站建设 专业网站设计 成都网站建设 移动网站建设