Solved

Oracle, tablespace

Posted on 2011-09-29
7
350 Views
Last Modified: 2012-05-12
how do i find -- the  true free space within the used portion of the tablespace? After a delete which delets not only the data but also lob data..
0
Comment
Question by:Rao_S
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
  • 2
7 Comments
 
LVL 77

Expert Comment

by:slightwv (䄆 Netminder)
ID: 36817369
Free for what?

Free for additional rows in the same table or free for other objects in the same tablespace?

If you delete rows from a table all you do is free up space for additional rows for that table.  Are you wanting to calculate how many rows can be inserted into the freed up space fbefore another Extent is allocated?

0
 
LVL 7

Accepted Solution

by:
Jacobfw earned 400 total points
ID: 36817390
this script is a good example

http://gavinsoorma.com/2009/07/script-tablespace-free-space-and-fragmentation/

Remember that deleting records (even ones that contain LOB columns does not free space necessarily.

This article provides an excellent overview of reclaiming space:
http://www.dba-oracle.com/t_reclaiming_disk_space.htm

For LOB's, you often need to "SHRINK" the table and the LOB seperately.

Like this:

Alter table DOCUSHARE.accesstable enable row movement;
/
-- Check if Shrink can be performed
ALTER TABLE tablename SHRINK SPACE CHECK;

Alter table tablename shrink space CASCADE;

Alter table tablename modify LOB (LOB_name)  (shrink space);
0
 

Author Comment

by:Rao_S
ID: 36817406
i read about the 'shrink' and then i got confused because thee is a pre requisite that the tablespace be 'assm' and i dont knoe how the tbspace is defined on our system..
0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:Rao_S
ID: 36817417
this query shows the true free space..in the temp tbspace... is there a query imilar to find the true used/free space...in a tbspace..?
-- To report true free space within the used portion of the TEMPFILE:
SELECT   A.tablespace_name tablespace, D.mb_total,
         SUM (A.used_blocks * D.block_size) / 1024 / 1024 mb_used,
         D.mb_total - SUM (A.used_blocks * D.block_size) / 1024 / 1024 mb_free
FROM     v$sort_segment A,
         (
         SELECT   B.name, C.block_size, SUM (C.bytes) / 1024 / 1024 mb_total
         FROM     v$tablespace B, v$tempfile C
         WHERE    B.ts#= C.ts#
         GROUP BY B.name, C.block_size
         ) D
WHERE    A.tablespace_name = D.name
GROUP by A.tablespace_name, D.mb_total;
0
 
LVL 77

Assisted Solution

by:slightwv (䄆 Netminder)
slightwv (䄆 Netminder) earned 100 total points
ID: 36817446
>>and i dont knoe how the tbspace is defined on our system..

select TABLESPACE_NAME, SEGMENT_SPACE_MANAGEMENT, EXTENT_MANAGEMENT
from dba_tablespaces;

>>this query shows the true free space..

That is unallocated space.  space from deleting data will not be shown.

For unallocated free space the view you are after is dba_free_space
0
 
LVL 7

Assisted Solution

by:Jacobfw
Jacobfw earned 400 total points
ID: 36817459
SELECT tablespace_name, extent_management, segment_space_management
FROM dba_tablespaces

Where segment_space_management = AUTO indicates ASSM

0
 

Author Closing Comment

by:Rao_S
ID: 36942226
thank you...the links given by Jacobfw!!
0

Featured Post

Free Tool: IP Lookup

Get more info about an IP address or domain name, such as organization, abuse contacts and geolocation.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Component is listed with a Protocol more than once 3 47
Fill Null values 5 36
update statement in oracle 9 40
How to drop system generated virtual column in a table in12c 15 116
This post first appeared at Oracleinaction  (http://oracleinaction.com/undo-and-redo-in-oracle/)by Anju Garg (Myself). I  will demonstrate that undo for DML’s is stored both in undo tablespace and online redo logs. Then, we will analyze the reaso…
Using SQL Scripts we can save all the SQL queries as files that we use very frequently on our database later point of time. This is one of the feature present under SQL Workshop in Oracle Application Express.
This video explains at a high level about the four available data types in Oracle and how dates can be manipulated by the user to get data into and out of the database.
This video shows how to recover a database from a user managed backup

756 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question