SYS@ bys3>alter database datafile '/u01/oradata/bys3/user01.dbf' autoextend on;
Database altered.
SYS@ bys3>select file_name,bytes/1024/1024 total_MB,user_bytes/1024/1024 user_mb,AUTOEXTENSIBLE from dba_data_files;
FILE_NAME TOTAL_MB USER_MB AUT
---------------------------------------- ---------- ---------- ---
/u01/oradata/bys3/sysaux01.dbf 325 324 YES
/u01/oradata/bys3/undotbs01.dbf 200 199 NO
/u01/oradata/bys3/user01.dbf 50 49 YES