Oracle's undotbs01.dbf file is too big a solution __oracle

How to log on to Oracle's Sql*plus with SYS users:
Sys
Oracle
ORCL as Sysdba

Oracle's UNDOTBS01.DBF file is too big a solution:

--Create a new small space for the undo Tablespace
CREATE UNDO tablespace UNDOTBS2 datafile ' D:/oracle/oradata/orcl/undotbs02. DBF ' SIZE 100M reuse autoextend on;
--Set the new table space for the system Undo_tablespace
ALTER SYSTEM SET UNDO_TABLESPACE=UNDOTBS2;
--DROP the old table space
DROP tablespace UNDOTBS1 including CONTENTS;
SELECT * from Dba_tablespaces;

Delete D:/oracle/oradata/orcl/undotbs01 when finished. DBF, and then perform the following operation:

--Create a new small space for the undo Tablespace
CREATE UNDO tablespace UNDOTBS1 datafile ' d:/oracle/oradata/orcl/undotbs01. DBF ' SIZE 100M reuse autoextend on;
--Set the new table space for the system Undo_tablespace
ALTER SYSTEM SET undo_tablespace=undotbs1;
--DROP the old table space
DROP tablespace UNDOTBS2 including CONTENTS;
--View all table spaces
SELECT * from Dba_tablespaces;

Delete D:/oracle/oradata/orcl/undotbs02 when finished. Dbf.

If the temporary table space is very large to handle the same method.