OracleStudy之案例--OracleASSM管理方式下的BITMAP
内容导读
互联网集市收集整理的这篇技术教程文章主要介绍了OracleStudy之案例--OracleASSM管理方式下的BITMAP,小编现在分享给大家,供广大互联网技能从业者学习和参考。文章包含3009字,纯文字阅读大概需要5分钟。
内容图文
![OracleStudy之案例--OracleASSM管理方式下的BITMAP](/upload/InfoBanner/zyjiaocheng/555/d351f4696a644ecbbe673f2b17e4b23f.jpg)
OracleStudy之案例--OracleASSM管理方式下的Bitmap在基于此在LMT(ExtentLocalManagement)下Oracle建议我们使用ASSM(AutomaticSegment-SpaceManagement),看看
Oracle Study之案例--Oracle ASSM管理方式下的Bitmap
在基于此在LMT(Extent Local Management)下Oracle建议我们使用ASSM(Automatic Segment-Space Management),看看
Oracle doc是如何来解释ASSM的:
This keyword tells Oracle that you want to use bitmaps to manage the free space with in segments. A bitmap, in this case, is a map that describes the status of each data block within a segment with respect to the amount of space in the block available for inserting rows. As more or less space becomes available in a data block, its new state is reflected in the bitmap. Bitmaps enable Oracle to manage free space more automatically; thus, this form of space management is called automatic segment-space management. Locally managed tablespaces using automatic segment-space management can be created as smallfile (traditional) or bigfile tablespaces. AUTO is the default.
案例分析:
1、查看emp表存储信息
17:31:39 SYS@ test1 >col segment_name for a20 17:33:01 SYS@ test1 >select owner,segment_name,segment_type,tablespace_name,bytes/1024 from dba_segments 17:33:24 2 where segment_name='EMP'; OWNER SEGMENT_NAME SEGMENT_TYPE TABLESPACE_NAME BYTES/1024 ------------------------------ -------------------- ------------------ ------------------------------ ---------- SCOTT EMP TABLE USERS 64 17:31:06 SYS@ test1 >select tablespace_name,contents,extent_management,SEGMENT_SPACE_MANAGEMENT from dba_tablespaces; TABLESPACE_NAME CONTENTS EXTENT_MAN SEGMEN ------------------------------ --------- ---------- ------ SYSTEM PERMANENT DICTIONARY MANUAL USERS PERMANENT LOCAL AUTO 17:37:42 SYS@ test1 >COL OWNER FOR A10 17:37:54 SYS@ test1 >R 1 select owner,SEGMENT_NAME,EXTENT_ID, FILE_ID,BLOCK_ID,BLOCKS from dba_extents 2* where segment_name='EMP' OWNER SEGMENT_NAME EXTENT_ID FILE_ID BLOCK_ID BLOCKS ---------- -------------------------------------------------- ---------- ---------- ---------- ---------- SCOTT EMP 0 4 144 8 17:16:05 SYS@ test1 >select header_file,header_block,blocks,extents from dba_segments where segment_name='EMP'; HEADER_FILE HEADER_BLOCK BLOCKS EXTENTS ----------- ------------ ---------- ---------- 4 146 8 12、对emp表中的block进行dump分析
17:39:30 SYS@ test1 >alter system dump datafile 4 block min 144 block max 151;
System altered.
查看dump的trace文件:
[oracle@RH6 ~]$ ls -lt /u01/app/oracle/diag/rdbms/test1/test1/trace/|more
total 56908
-rw-r----- 1 oracle oinstall 25923 Dec 15 17:42 test1_ora_2385.trc
内容总结
以上是互联网集市为您收集整理的OracleStudy之案例--OracleASSM管理方式下的BITMAP全部内容,希望文章能够帮你解决OracleStudy之案例--OracleASSM管理方式下的BITMAP所遇到的程序开发问题。 如果觉得互联网集市技术教程内容还不错,欢迎将互联网集市网站推荐给程序员好友。
内容备注
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 gblab@vip.qq.com 举报,一经查实,本站将立刻删除。
内容手机端
扫描二维码推送至手机访问。