Oracle Database Discussions

Hi

dbms_space.create_index_cost can help you

I haven't created yet! But I can still run this proc? BTW, I am in Oracle 9.2

Looks like Oracle 9.2 doesn't have it,

<pre>
SQL> desc dbms_space.create_index_cost
ERROR:
ORA-04043: object dbms_space.create_index_cost does not exist
</pre>

Thanks Mark. That's about it. :)

You are welcome. Thank you for the points. If you get to build the index soon and can remember post back with the actual results.

-- mark --

Yes is it to known the future size BEFORE create index by using statistics

look the Ask Tom http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:1833377500346797242

for psoug this package exist since 7.3.4. I use it on 10.2.0[2-4] and 11g ({ORACLE_HOME}/rdbms/admin/dbmsspu.sql)
http://psoug.org/reference/dbms_space.html

my test also :
SQL*Plus: Release 11.1.0.6.0
SYS@SGA>create table tsygale as select level num from dual connect by level<=100000;

Table created.
SYS@SGA>@seg_tab
Enter value for segment_name: TSYGALE
old 3: where segment_name in ('&segment_name')
new 3: where segment_name in ('TSYGALE')

TABLESPACE_NAME SEGMENT_NAME MO
-------------------- ----------------------------------- ----------
SYSTEM TSYGALE 2
SYS@SGA>exec dbms_stats.gather_table_stats(user,'TSYGALE');

PL/SQL procedure successfully completed.

Elapsed: 00:00:02.95

SYS@SGA>variable used number
SYS@SGA>variable alloc number
exec dbms_space.create_index_cost( 'create index isygale on tsygale(object_name,object_type,owner)', :used, :alloc );

PL/SQL procedure successfully completed.

Elapsed: 00:00:00.25
16:56:38 SYS@SGA>print used

USED
----------
2761720

16:56:49 SYS@SGA>print alloc

ALLOC
----------
4194304
SYS@SGA>create index isygale on tsygale(object_name,object_type,owner);

Index created.

Elapsed: 00:00:00.50

SYS@SGA>@seg_tabind
Segment name ?TSYGALE
old 3: where (segment_name in ('&&segment_name')
new 3: where (segment_name in ('TSYGALE')
old 5: segment_name in (select index_name from dba_indexes where table_name in ('&&segment_name'))
new 5: segment_name in (select index_name from dba_indexes where table_name in ('TSYGALE'))

TABLESPACE_NAME SEGMENT_TYPE SEGMENT_NAME MO
-------------------- ------------------ ----------------------------------- ----------
SYSTEM TABLE TSYGALE 8
SYSTEM INDEX ISYGALE 4

Elapsed: 00:01:22.31


So package estimate to 4 194 304 Octets and after the index created the size is to 4MO, so ....

Edited by: Sygale on Apr 8, 2010 5:02 PM

Unfortunately the OP says he is using 9.2, and although the package has been around since 7.3 that particular procedure was not introduced until 10g - and it has a couple of flaws built in, see: http://jonathanlewis.wordpress.com/2009/05/22/index-size/

Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk

To post code, statspack/AWR report, execution plans or trace files, start and end the section with the tag {noformat}

{noformat} (lowercase, curly brackets, no spaces) so that the text appears in 

fixed format

.

There is a +"Preview"+ tab at the top of the text entry panel. Use this to check what your message will look like before you post the message. If it looks a complete mess you're unlikely to get a response. (Click on the +"Plain text"+ tab if you want to edit the text to tidy it up.)

+"I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I'll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be."+
Isaac Asimov                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

Sorry for this mistake, have you a method to define on which version a functionality is delivered ?

I read your article, I see some errors in this package,
but it can help us to define if we have enough space on disk to create index or table in Clone environment. Before create it on production ;)

A real test is always better than an estimate test

I recommend to add 10% margin from development to production (the production database is always run ;))

Thanks