ALTER TABLESPACE users  
  
ADD DATAFILE 'D:/oracle/oradata/orcl/users.dbf' SIZE 500M  
  
AUTOEXTEND ON  
  
NEXT 50M  
  
MAXSIZE 2000M; 

 

Select Tablespace_Name,Sum(bytes)/1024/1024 From Dba_Segments Group By Tablespace_Name