How to enable autoextend on a datafile in Oracle

Let a datafile grow on its own up to a ceiling instead of erroring when it fills.

This changes datafile growth behavior. Review the increment and max size before running.

ALTER DATABASE DATAFILE '&&datafile_path'
  AUTOEXTEND ON NEXT 256M MAXSIZE 16G;

-- To turn it off:
-- ALTER DATABASE DATAFILE '&datafile_path' AUTOEXTEND OFF;

-- Verify (read-only)
SELECT file_name, autoextensible, ROUND(bytes/1024/1024) AS size_mb,
       ROUND(maxbytes/1024/1024) AS max_mb, increment_by
FROM   dba_data_files
WHERE  file_name = '&datafile_path';