[bbk5208] 第109集 -第13章 - 表空间管理 07

Reclamining Space Within ASSM Segments

• Online and in-place operation
• Applicable only to segments residing in ASSM tablespaces
• Candidate segment types:
  • Heap-organized tables and index-organized tables
  • Indexes
  • Partitions and subpartitions
  • Materialized views and materialized view logs

Segment Advisor:Overview

Managing Resumable Space Allocation

A resumable statement:

• Enables you to suspend large operations instead of receiving an error
• Gives you a chance to fix the problem while the operation is suspended,rather than starting over
• Is suspended for the following conditions
  • Out of space
  • Maxmum extents reached
  • Space quota exceeded
• A resumable statement can be suspended and resumed multiple times.

 

• Online and in-place operation

使用ASSM回收空间，支持在线操作并且不需要分配额外的表空间分配，即可实现.

• Applicable only to segments residing in ASSM tablespaces

只有采用了ASSM的表空间，才可以使用自动收缩功能. 

表中带有long类型的，也不支持收缩.

On commited materialized view也是不支持收缩的.

包含了基于函数的索引表，也不支持收缩.

Segment Advisor：擅长段空间管理，节约空间，提高效率.

Segment Advisor检查AWR中的数据，进行采样分析，寻找可以回收的空间，产生报告;

调用方式：自动执行(ADDM执行完成之后，自动执行段管理专家)

　　　　手工的执行

如何手工回收段空间？参照博文http://www.cnblogs.com/arcer/archive/2013/06/09/3128171.html