Why not use SELECT * FROM XXX (Oracle Pro Test)

Open used Time
Set timing on;
CREATE table users (ID number), name varchar2, password varchar2 (20));
Insert into users values (111111111111111, ' Enuero Qi star ', ' [email protected] ');
INSERT into users (ID, name, password) select * from users; Insert 32,768 piece of data
select * from Users; spents 40.58 seconds
Select name from users; spents 23.34 seconds
select * from Users; spents 38.58 seconds
Select name from users; spents 23.91 seconds
select * from Users; spents 39.47 seconds
Select name from users; spents 24.28 seconds

Why not use SELECT * FROM XXX (Oracle Pro Test)