Oracle Database Discussions

Hello,

I am doing some R&D and want to create a Table with 1 row, which is 1 MB in size.

i.e. I want to create a row which is 1 MB in size.

I am using a 11g DB.

I do this in SQL*Plus:

(1.) CREATE TABLE onembrow  (pk NUMBER PRIMARY KEY, onembcolumn CLOB);

(2.) Since 1MB is 1024*1024 bytes (i.e. 1048576 bytes) and since in English 1 letter = 1 byte, I do this

SQL> INSERT INTO onembrow VALUES (1, RPAD('A', 1048576, 'B'));

1 row created.

(3.) Now, after committing, I do an analyze table.

SQL> ANALYZE TABLE onembrow COMPUTE STATISTICS;

Table analyzed.

(4.) Now, I check the actual size of the table using this query.

select segment_name,segment_type,bytes/1024/1024 MB

from user_segments where segment_type='TABLE' and segment_name='ONEMBROW';

------------------------- ------------------ ----------

Why is the size only .0625 MB, when it should be 1 MB?

Here is the DB Block related parameters:

SELECT * FROM v$parameter WHERE upper(name) LIKE '%BLOCK%';

  NUM NAME                                                                                   TYPE VALUE 

----- -------------------------------------------------------------------------------- --------

  478 db_block_buffers                                                                          3 0     

  482 db_block_checksum                                                                         2 TYPICAL

  484 db_block_size                                                                             3 8192  

  682 db_file_multiblock_read_count                                                             3 128   

  942 db_block_checking                                                                         2 FALSE 

What am I doing wrong here???