| Confusion with initial extent in Uniform LMT [message #248802] |
Mon, 02 July 2007 01:31  |
sureshkay
Messages: 21
Registered: June 2007
|
Junior Member |
|
|
As per Oracle Documentation
Reference :
http://download-uk.oracle.com/docs/cd/B19306_01/server.102/b14200/clauses009.htm
[In locally managed tablespaces, Oracle uses the value of INITIAL in conjunction with the size of extents specified for the tablespace to determine the first extent of the object.
For example, in a uniform locally managed tablespace with 5M extents, if you specify an INITIAL value of 1M, then Oracle creates five 1M extents.]
To check this statement I exercised it in practice
I created a Locally managed Tablespace with uniform size 5M.
create tablespace ts_test01
datafile 'e:\df_test01.dbf' size 40M
extent management local uniform size 5M
Then I created a table in that tablespace with initial extent 1M as said in example.
Create table T_TEST01 (I number)
Storage (initial 1M);
Now when I query the dba_extents I find Only 1 Extent with ID 0 having 5M Size.
select segment_name, tablespace_name, extent_id, bytes, blocks from user_extents
SEG_NAM TABSPA_NAME EXT_ID BYTES BLOCKS
---------- --------------------- ---------- -----
T_TEST01 TS_TEST01 0 5242880 640
But as per Oracle documentation there should be 5 Extents with 1M size.
So is there any thing wrong in my interpretation ???
Also when I create tablespace with uniform size 1M
create tablespace ts_test02
datafile 'e:\df_test02.dbf' size 40M
extent management local uniform size 1M
and Then create a table of Initial size 5M
Create table T_TEST01 (I number)
Storage (initial 5M);
Now when I query the dba_extents I find 5 Extents with ID 0,1,2,3,4 having each 1M Size.
select segment_name, tablespace_name, extent_id, bytes, blocks from user_extents
SEG_NAM TABSPA_NAME EXT_ID BYTES BLOCKS
-------------- --------------------- ----------
T_TEST01 TS_TEST02 0 1048576 128
T_TEST01 TS_TEST02 1 1048576 128
T_TEST01 TS_TEST02 2 1048576 128
T_TEST01 TS_TEST02 3 1048576 128
T_TEST01 TS_TEST02 4 1048576 128
[Updated on: Mon, 02 July 2007 02:11] Report message to a moderator |
|
|
|
|
|
| Re: Confusion with initial extent in Uniform LMT [message #248813 is a reply to message #248810] |
Mon, 02 July 2007 02:28  |
sureshkay
Messages: 21
Registered: June 2007
|
Junior Member |
|
|
Thanx Michel,
But Are u sure, or is there anything wrong with my interpretation. I will wait for any more comments before i am sure.
The Storage Clause for Tables with LMT is having very much confusion.
Effect of INITIAL, NEXT, MINEXTENTS, MAXEXTENTS,PCTINCREASE, MINIMUM EXTENT on Allocation of Extents For
UNIFORM LMT:
AUTOALLOCATE LMT:
DMT:
Can anyone put it in simple words.
Thanx in Advance with many many interests
|
|
|
|
|
|
] 
Blog
Search
Help
Members
Register
Login
Home
