Re: free space

From: Jurij Modic <jmodic_at_src.si>
Date: Mon, 02 Nov 1998 19:19:02 GMT
Message-ID: <363e037e.6290137@news.siol.net>

On Sun, 01 Nov 1998 15:32:45 +0100, Sybrand Bakker <postbus_at_sybrandb.demon.nl> wrote:

>What your are looking at is free extents in your database. Contiguous
>extents are combined afaik in the view, all extents reported here should
>be non-contiguous. So you are looking at a database with very little and a
>bit fragmented free-space. The 2 block extents in DATA01 are probably
>never to be used anymore as the minimum segment is 5 Oracle blocks.

I don't want to be hair-splitting, but you can define extent to be as small as you want, down to 2 db blocks! So Doug will be able to use even those 2 block extents if he wants to have such small extents.

Here is an example (db_block_size=2K):

SQL> CREATE TABLE test_1 (c1 NUMBER) STORAGE(INITIAL 2K);

Table created.

SQL> CREATE TABLE test_2 (c1 NUMBER) STORAGE(INITIAL 4K);

Table created.

SQL> CREATE TABLE test_3 (c1 NUMBER) STORAGE(INITIAL 6K);

Table created.

SQL> SELECT SUBSTR(segment_name,1,10), extent_id, bytes, blocks   2 FROM user_extents WHERE segment_name LIKE 'TEST%';

SUBSTR(SEG EXTENT_ID BYTES BLOCKS ---------- ---------- ---------- ----------

TEST_1              0       4096          2
TEST_2              0       4096          2
TEST_3              0       6144          3

>Hth,
>Sybrand Bakker, Oracle DBA

Regards,
Jurij Modic <jmodic_at_src.si>
Certified Oracle7 DBA (OCP)

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The above opinions are mine and do not represent any official standpoints of my employer Received on Mon Nov 02 1998 - 13:19:02 CST