Oracle: Restrict / Check / Fixed column values while creating table

Set Default Values

Examples:

CREATE TABLE ExampleTable
(
   Id int NOT NULL,
   Frequency varchar2(200) default 'Daily');

ALTER TABLE exampleTable ADD COLUMN new_column VarChar2(20) DEFAULT 'value1';

To Fixed / Check / Restrict values for Column

Examples:

CREATE TABLE ExampleTable
(
   Id int NOT NULL,
   Frequency varchar2(200),
   CONSTRAINT chk_Frequency CHECK (Frequency IN ('Daily', 'Weekly', 'Monthly', 'Yearly'))
);

alter table ExampleTable
    add (new_column varchar2(20) default 'value1',
         constraint ckExampleTable check (new_column in ('value1', 'value2', 'value3')));