-- files with autoextend on
set linesize 120
col tablespace_name for a40
col file_name for a50
col autoextensible for a15
select tablespace_name, file_name, bytes/1024/1024 MB, autoextensible from dba_data_files where autoextensible='YES' order by tablespace_name, file_name
/
-- generate SQL to disable autogrow
select 'ALTER DATABASE DATAFILE ''' || file_name  || ''' AUTOEXTEND OFF;' from  dba_data_files where autoextensible='YES' order by tablespace_name, file_name
/

-- disable autoextend (datafile autogrow)
alter database datafile '/oradata/file.dbf' RESIZE 2500M;
alter database datafile '/oradata/file.dbf' autoextend off;