select a.FILE_NAME,a.AUTOEXTENSIBLE,a.MAXBYTES,a.INCREMENT_BY from dba_data_files a;
--AUTOEXTENSIBLE 是否自动扩展
--MAXBYTES 最大
--INCREMENT_BY 自动扩展块数
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 块大小*块数=自动扩展的大小;
例:
create tablespace sq01 datafile 'd:\sq01.bdf' size 5m ; --创建表空间
alter database datafile 'd:\sq01.bdf' autoextend on next 20m maxsize 100m;
--修改表空间自动增长每次增长20m最大空间100M
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