Originally posted by sreddy
Did you test this behaviour or you are talking on theoritical/documentation grounds ?
i have tested it on permanent LMT with uniform size and system managed LMT but not on Temporary LMTs.

The result is based on permanent LMT . So i assume that extent allocation would be same in Temporary LMT as in Permanent LMTs.

Code:
[email protected]D> create tablespace SYSTEM_MANAGED datafile      
  2  ‘e:\oracle\oradata\orcl\test01.dbf’ size 50M
  3  extent management local;

Tablespace created.

[email protected]D> create table big_table_system tablespace SYSTEM_MANAGED as select * from scott.voyages;

Table created.

[email protected]D> select tablespace_name, extent_id, bytes/1024,blocks from user_extents where segment_name ='BIG_TABLE_SYSTEM';

TABLESPACE_NAME                 EXTENT_ID BYTES/1024     BLOCKS
------------------------------ ---------- ---------- ----------
SYSTEM_MANAGED                          0         64          8
SYSTEM_MANAGED                          1         64          8
.
.
SYSTEM_MANAGED                         14         64          8
SYSTEM_MANAGED                         15         64          8
SYSTEM_MANAGED                         16       1024        128
SYSTEM_MANAGED                         17       1024        128
.
.
SYSTEM_MANAGED                         77       1024        128
SYSTEM_MANAGED                         78       1024        128
SYSTEM_MANAGED                         79       8192       1024
SYSTEM_MANAGED                         80       8192       1024
SYSTEM_MANAGED                         81       8192       1024
SYSTEM_MANAGED                         82       8192       1024

83 rows selected.
Here you can see – the first 16 extents are each 64K in size. The next 63 each 1M in size and the remaining are 8M in size. As the object grew – the extents grew as well. That is a total of about 99M of space in there – in 83 extents.

Code:
[email protected]D> create tablespace UNIFORM_SIZE datafile
  2  'e:\oracle\oradata\orcl\test01.dbf' size 100M
  3  Extent management local
  4  Uniform size 5M
  5  /

[email protected]D> create table big_table_uniform tablespace UNIFORM_SIZE as select * from scott.rd_voyages;

Table created.

[email protected]D> select tablespace_name, extent_id, bytes/1024,blocks from user_extents where segment_name ='BIG_TABLE_UNIFORM';

TABLESPACE_NAME                 EXTENT_ID BYTES/1024     BLOCKS
------------------------------ ---------- ---------- ----------
UNIFORM_SIZE                            0       5120        640
UNIFORM_SIZE                            1       5120        640
UNIFORM_SIZE                            2       5120        640
UNIFORM_SIZE                            3       5120        640
UNIFORM_SIZE                            4       5120        640
UNIFORM_SIZE                            5       5120        640 
UNIFORM_SIZE                            6       5120        640
UNIFORM_SIZE                            7       5120        640
UNIFORM_SIZE                            8       5120        640
UNIFORM_SIZE                            9       5120        640
UNIFORM_SIZE                           10       5120        640
UNIFORM_SIZE                           11       5120        640
UNIFORM_SIZE                           12       5120        640
UNIFORM_SIZE                           13       5120        640
UNIFORM_SIZE                           14       5120        640
UNIFORM_SIZE                           15       5120        640
UNIFORM_SIZE                           16       5120        640
UNIFORM_SIZE                           17       5120        640
UNIFORM_SIZE                           18       5120        640

19 rows selected.
As expected - each and every extent is 5MB, every extent ever allocated in this tablespace will be 5MB, not a byte more not a byte less.

I agree that I haven't tested on temporary LMTs, in fact i have been thinking about it... Can any one let me know how do i see the temporary extents , That would help me prove if my thinking is right or wrong.

Cheers