一、Oracle查看 表空间 的名称及其大小
查看 表空间的名称及其大小的SQL语句：
select t1.tablespace_name,round(sum(bytes/(1024*1024)),0) tablespace_Size_MB
from dba_tablespaces t1, dba_data_files t2
where t1.tablespace_name = t2.tablespace_name
group by t1.tablespace_name;
查询结果：
TABLESPACE_NAME TABLESPACE_SIZE_MB
------------------------------ ------------------
DLOTTEY 276480
SYSAUX 48450
UNDOTBS1 20000
INDEXMT 10240
USERS 1041
SYSTEM 10240
UNDOTBS2 20000
MMLOTTERY 215040 8 rows selected.
二、Oracle查看 表空间 的具体使用情况
方法1：（未排序）
select a.tablespace_name "tablespace_name",
totalspace "totalspaceM",
freespace "freespaceM",
round((1-freespace/totalspace)*100,2) "round%"
from
(select tablespace_name,round(sum(bytes)/1024/1024) totalspace from dba_data_files group by tablespace_name) a,
(select tablespace_name,round(sum(bytes)/1024/1024) freespace from dba_free_space group by tablespace_name) b
where a.tablespace_name=b.tablespace_name;
查询结果：
tablespace_name totalspaceM freespaceM round%
------------------------ ----------- ---------- ----------
DLOTTEY 276480 232415 15.94
SYSAUX 48450 9683 80.01
UNDOTBS1 20000 19741 1.3
INDEXMT 10240 10024 2.11
USERS 1041 138 86.74
SYSTEM 10240 4344 57.58
UNDOTBS2 20000 19601 2
MMLOTTERY 215040 36279 83.13 8 rows selected.
方法二：（查询结果排序）
select a.tablespace_name,
a.bytes/1024/1024 "Sum MB",
(a.bytes-b.bytes)/1024/1024 "used MB",
b.bytes/1024/1024 "free MB",
round(((a.bytes-b.bytes)/a.bytes)*100,2) "percent_used"
from
(select tablespace_name,sum(bytes) bytes from dba_data_files group by tablespace_name) a,
(select tablespace_name,sum(bytes) bytes,max(bytes) largest from dba_free_space group by tablespace_name) b
where a.tablespace_name=b.tablespace_name
order by ((a.bytes-b.bytes)/a.bytes) desc;
查询结果：
TABLESPACE_NAME Sum MB used MB free MB percent_used
---------------------- ---------- ---------- ---------- ------------
USERS 1041.25 903.375 137.875 86.76
MMLOTTERY 215040 178761 36279 83.13
SYSAUX 48450 38767 9683 80.01
SYSTEM 10240 5896.125 4343.875 57.58
DLOTTEY 276480 44065.4375 232414.563 15.94
INDEXMT 10240 215.625 10024.375 2.11
UNDOTBS2 20000 399.3125 19600.6875 2
UNDOTBS1 20000 257.5 19742.5 1.29 8 rows selected.
三、Oracle查看 表空间物理文件 的名称及大小
set lines 150;
col tablespace_name for a20;
col file_name for a60;
1、查询所有的表空间
SQL语句：
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space_MB
from dba_data_files
order by tablespace_name;
2、查询指定的表空间
SQL语句：
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space_MB
from dba_data_files
where tablespace_name = 'MMLOTTERY'
order by tablespace_name;
查询结果：
TABLESPACE_NAME FILE_ID FILE_NAME TOTAL_SPACE_MB
------------------- ---------- ------------------------------------------- --------------
MMLOTTERY 18 +DATA/ora11g/datafile/mmlottery01.dbf 30720
MMLOTTERY 19 +DATA/ora11g/datafile/mmlottery02.dbf 30720
MMLOTTERY 20 +DATA/ora11g/datafile/mmlottery03.dbf 30720
MMLOTTERY 22 +DATA/ora11g/datafile/mmlottery04.dbf 30720
MMLOTTERY 23 +DATA/ora11g/datafile/mmlottery05.dbf 30720
MMLOTTERY 26 +DATA/ora11g/datafile/mmlottery06.dbf 30720
MMLOTTERY 27 +DATA/ora11g/datafile/mmlottery07.dbf 30720 7 rows selected.
四、Oracle查看 表 真实占用的空间
SQL语句：
select t.owner,t.segment_name,t.segment_type,
sum(t.bytes/1024/1024) used_MB
from dba_segments t
where owner = 'MMLOTTERY'
group by owner,segment_name,segment_type
order by used_MB desc;
查询结果：
OWNER SEGMENT_NAME SEGMENT_TYPE USED_MB
------------------- -------------------------------- ------------------ ----------
MMLOTTERY TB_ORIGINAL_ORDERDETAILS TABLE 1792
MMLOTTERY TB_LOTTERY_SALEDETAIL TABLE 1472
MMLOTTERY TB_LOTTERYSCHEMEINFO_ADD TABLE 1280
MMLOTTERY TEST_007 TABLE 1152
MMLOTTERY TB_ACCOUNT_OPERATE_DETAIL TABLE 808
MMLOTTERY PK14 INDEX 377
MMLOTTERY PK14_11 INDEX 312
MMLOTTERY PK14_13 INDEX 200
MMLOTTERY PK14_12 INDEX 160
MMLOTTERY TB_BONUS_ORDERDETAILS TABLE 160
MMLOTTERY TB_WINBONUS_DETAIL TABLE 144 11 rows selected.
五、Oracle 增加表空间
语法：
alter tablespace {表空间名字} add datafile '物理数据文件路径' SIZE 『初始大小M』 AUTOEXTEND ON NEXT 『自动扩展大小M』
例子：
alter tablespace MMLOTTERY add datafile '+DATA/ora11g/datafile/mmlottery08.dbf' size 30720m autoextend on next 200m;
注意：如果添加表空间的文件名重复，那么会报错，如下：
SQL> alter tablespace MMLOTTERY add datafile '+DATA/ora11g/datafile/mmlottery08.dbf' size 30720m autoextend on next 200m;
alter tablespace MMLOTTERY add datafile '+DATA/ora11g/datafile/mmlottery08.dbf' size 30720m autoextend on next 200m
*
ERROR at line 1:
ORA-01537: cannot add file '+DATA/ora11g/datafile/mmlottery08.dbf' - file already part of database
若 datafile 加错到表空间，则执行删除操作。
alter tablespace MMLOTTERY drop datafile '+DATA/ora11g/datafile/mmlottery08.dbf';
或者
alter database datafile '+DATA/ora11g/datafile/mmlottery08.dbf' offline drop;
六、Oracle 临时表空间的查看与增加
查看临时表空间
SQL语句：
select tablespace_name,file_id,file_name,round(bytes/1024/1024,0) temp_size_MB from dba_temp_files;
查询结果：
TABLESPACE_NAME FILE_ID FILE_NAME TEMP_SIZE_MB
----------------- ---------- --------------------------------------------- ------------
TEMP 1 +DATA/ora11g/tempfile/temp.262.917714589 20000
增加临时表空间文件
SQL语句：
alter tablespace TEMP add tempfile '+DATA/ora11g/tempfile/temp01.dbf' size 20000m autoextend on next 2000m;
七、查看表空间是否为自增
表空间是有数据文件组成的，所以看表空间是否自增即看数据文件，如下查自增的表空间：
select tablespace_name,file_name,autoextensible from dba_data_files where autoextensible='YES';
autoextensible: YES/NO 即表示是否自增。
示例：
SQL> select tablespace_name,file_name,autoextensible from dba_data_files where TABLESPACE_NAME='USERS'; TABLESPACE_NAME FILE_NAME AUT
-------------------- ------------------------------------------------------------ ---
USERS +DATA/ora11g/datafile/users.264.917714693 YES
【实例】Oracle 表空间的查看与增加
步骤 1、查看表空间的具体使用情况
SQL语句，如下：
select a.tablespace_name,
a.bytes/1024/1024 "Sum MB",
(a.bytes-b.bytes)/1024/1024 "used MB",
b.bytes/1024/1024 "free MB",
round(((a.bytes-b.bytes)/a.bytes)*100,2) "percent_used"
from
(select tablespace_name,sum(bytes) bytes from dba_data_files group by tablespace_name) a,
(select tablespace_name,sum(bytes) bytes,max(bytes) largest from dba_free_space group by tablespace_name) b
where a.tablespace_name=b.tablespace_name
order by ((a.bytes-b.bytes)/a.bytes) desc;
查询结果：
TABLESPACE_NAME Sum MB used MB free MB percent_used
---------------------- ---------- ---------- ---------- ------------
USERS 1041.25 903.375 137.875 86.76
MMLOTTERY 215040 178761 36279 83.13
SYSAUX 48450 38767 9683 80.01
SYSTEM 10240 5896.125 4343.875 57.58
DLOTTEY 276480 44065.4375 232414.563 15.94
INDEXMT 10240 215.625 10024.375 2.11
UNDOTBS2 20000 399.3125 19600.6875 2
UNDOTBS1 20000 257.5 19742.5 1.29 8 rows selected.
步骤2、查看指定表空间（MMLOTTERY）的物理文件名称及其大小
set lines 150;
col tablespace_name for a20;
col file_name for a60;
SQL语句：
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space_MB
from dba_data_files
where tablespace_name = 'MMLOTTERY'
order by tablespace_name;
查询结果：
TABLESPACE_NAME FILE_ID FILE_NAME TOTAL_SPACE_MB
------------------- ---------- ------------------------------------------- --------------
MMLOTTERY 18 +DATA/ora11g/datafile/mmlottery01.dbf 30720
MMLOTTERY 19 +DATA/ora11g/datafile/mmlottery02.dbf 30720
MMLOTTERY 20 +DATA/ora11g/datafile/mmlottery03.dbf 30720
MMLOTTERY 22 +DATA/ora11g/datafile/mmlottery04.dbf 30720
MMLOTTERY 23 +DATA/ora11g/datafile/mmlottery05.dbf 30720
MMLOTTERY 26 +DATA/ora11g/datafile/mmlottery06.dbf 30720
MMLOTTERY 27 +DATA/ora11g/datafile/mmlottery07.dbf 30720 7 rows selected.
步骤3、增加指定表空间（MMLOTTERY）的大小
增加指定表空间的大小，SQL语句：
SQL> alter tablespace MMLOTTERY add datafile '+DATA/ora11g/datafile/mmlottery.dbf' size 30720m; Tablespace altered.
根据步骤2的命令，查询增加后的结果：
TABLESPACE_NAME FILE_ID FILE_NAME TOTAL_SPACE_MB
-------------------- ---------- ------------------------------------------------------------ --------------
MMLOTTERY 18 +DATA/ora11g/datafile/mmlottery01.dbf 30720
MMLOTTERY 19 +DATA/ora11g/datafile/mmlottery02.dbf 30720
MMLOTTERY 20 +DATA/ora11g/datafile/mmlottery03.dbf 30720
MMLOTTERY 22 +DATA/ora11g/datafile/mmlottery04.dbf 30720
MMLOTTERY 23 +DATA/ora11g/datafile/mmlottery05.dbf 30720
MMLOTTERY 26 +DATA/ora11g/datafile/mmlottery06.dbf 30720
MMLOTTERY 27 +DATA/ora11g/datafile/mmlottery07.dbf 30720
MMLOTTERY 28 +DATA/ora11g/datafile/mmlottery08.dbf 30720 8 rows selected.
步骤4、查看增加表空间后的具体情况
SQL语句：
select a.tablespace_name,
a.bytes/1024/1024 "Sum MB",
(a.bytes-b.bytes)/1024/1024 "used MB",
b.bytes/1024/1024 "free MB",
round(((a.bytes-b.bytes)/a.bytes)*100,2) "percent_used"
from
(select tablespace_name,sum(bytes) bytes from dba_data_files group by tablespace_name) a,
(select tablespace_name,sum(bytes) bytes,max(bytes) largest from dba_free_space group by tablespace_name) b
where a.tablespace_name=b.tablespace_name
and a.tablespace_name='MMLOTTERY';
查询结果：
TABLESPACE_NAME Sum MB used MB free MB percent_used
-------------------- ---------- ---------- ---------- ------------
MMLOTTERY 245760 179218 66542 72.92
【备注】
Oracle只查询一条记录的语句：
select * from tablename where rownum = 1;
修改用户默认表空间
alter user user_name default tablespace dev_tb;
alter user user_name temporary tablespace dev_temp;
查看数据文件是否有数据：
只需查看数据文件中是否包含extent段。如果有extent（索引段，数据段）段，则说明数据文件中有数据。
使用dba_extents视图和dba_data_files视图进行连接查询。
select t.file_name,t1.owner,t1.segment_name,t1.segment_type,t1.tablespace_name from dba_data_files t,dba_extents t1 where t.file_id=t1.file_id and file_name='你要查询的数据文件路径';