Alter table to drop unused columns : Alter Table « Table « Oracle PL / SQL






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Alter table to drop unused columns

   


create table people(
  employee_id     number(9),
  first_name      varchar2(15),
  last_name       varchar2(20),
  email           varchar2(25),
  constraint pk_people primary key (employee_id)
);

insert into people
values (1, 'Tom', 'Kyte', 'YourName@q.com');

insert into people
values (2, 'Sean', 'Viper', 'sdillon@q.com');

insert into people
values (3, 'Christopher', 'Beck', 'clbeck@q.com');

select * from people;

alter table people drop column first_name;

alter table people drop column last_name;

select * from user_unused_col_tabs;

ALTER TABLE people DROP UNUSED COLUMNS;

drop table people;








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