Alter table add column in Oracle

To add one or more columns to an Oracle table you can use the "alter table add column" command.

Syntax for adding 1 column:
alter table add ( );
(constraint is optional)

For example:
alter table customer add (mobile_phone varchar2(20) null);

Syntax for adding more columns:
alter table add ( ,
,
..
);
(constraints are optional)

For example:
alter table customer add (mobile_phone varchar2(20) null,
location_code varchar2(40));