1. 查看表空间是否自增长

　　SELECT FILE_NAME, TABLESPACE_NAME, AUTOEXTENSIBLE FROM DBA_DATA_FILES;

　　2. 查看表空间大小

　　select tablespace_name, sum(bytes) / 1024 / 1024 as MB from dba_data_files group by tablespace_name;

　　3. 查看表空间使用情况

　　select tablespace_name,count(*) as extends,round(sum(bytes) / 1024 / 1024, 2) as MB,sum(blocks) as blocks from dba_free_space group by tablespace_name;

　　4. 查看当前用户默认表空间

　　select username,default_tablespace from user_users;