Oracle tablespace automatic Expansion size ____oracle

Select a.file_name,a.autoextensible,a.maxbytes,a.increment_by from Dba_data_files A;

--autoextensible automatically expands--maxbytes maximum
--increment_by number of automatic expansion blocks

Sql> Show Parameter Db_block
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
Db_block_buffers integer 0
Db_block_checking Boolean FALSE
Db_block_checksum Boolean TRUE
Db_block_size integer 8192


--db_block_size*increment_by Block Size * block number = size of automatic expansion;



Example:
Create tablespace sq01 datafile ' d:\sq01.bdf ' size 5m; --Create a table space


ALTER DATABASE datafile ' D:\SQ01.BDF ' autoextend on next 20m maxsize 100m;
--Modify table space automatically grow 20m maximum space 100M per increment


Sql> Select a.file_name,a.autoextensible,a.maxbytes,a.increment_by from Dba_data_files A;

file_name autoextensible MaxBytes increment_by
-------------------------------------------------------------------------------- -------------- ---------- ------- -----
D:\SQ01. BDF YES 104857600 2560




Sql> Show Parameter Db_block

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
Db_block_buffers integer 0
Db_block_checking Boolean FALSE
Db_block_checksum Boolean TRUE
Db_block_size integer 8192


Sql> Select 2560*8192/1024/1024| | ' M ' from dual;

2560*8192/1024/1024| | ' M
------------------------

20M