Oracle10gR2新特性：删除空的数据文件

从Oracle10gR2版本起，oracle提供了删除tablespace中空数据文件的功能。

select">SYS@ning>select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod
PL/SQL Release 10.2.0.1.0 - Production
CORE 10.2.0.1.0 Production
TNS for 32-bit Windows: Version 10.2.0.1.0 - Production
NLSRTL Version 10.2.0.1.0 - Production

create">SYS@ning>create tablespace test datafile 'd:/test.ora' size 1m,'d:/test2.ora' size 1m;

Tablespace created.

alter">SYS@ning>alter tablespace test drop datafile 'd:/test2.ora';

Tablespace altered.

alter">SYS@ning>alter tablespace test add datafile 'd:/test2.ora' size 1m;

Tablespace altered.

create">SYS@ning>create table test(a char(2000),b char(2000),c char(2000),d char(2000))
2 tablespace test;

Table created.

insert">SYS@ning>insert into test values('a','b','c','d');

1 row created.

insert">SYS@ning>insert into test select * from test;

1 row created.

/">SYS@ning>/

2 rows created.

/">SYS@ning>/

4 rows created.

/">SYS@ning>/

8 rows created.

/">SYS@ning>/

16 rows created.

/">SYS@ning>/
insert into test select * from test
*
ERROR at line 1:
ORA-01653: unable to extend table SYS.TEST by 128 in tablespace TEST

alter">SYS@ning>alter tablespace test drop datafile 'd:/test2.ora';
alter tablespace test drop datafile 'd:/test2.ora'
*
ERROR at line 1:
ORA-03262: the file is non-empty

drop">SYS@ning>drop table test;

Table dropped.

alter">SYS@ning>alter tablespace test drop datafile 'd:/test2.ora';

Tablespace altered.