SQL set allowed values for a column I want to make an ALTER TABLE expression which adds a new column and sets a default value and additionaly defines the allowed values for that column. It's a text column, and allowed should be only 'value1', 'value2' and 'value3'. Default should be 'value1'

According to following syntax diagrams:






I'm getting to this point

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


but I'm absolutely not sure how to set the allowed values. 

Is it possible to make somethin like

CONSTRAINT CHECK new_column IN ('value1', 'value2', 'value3)

? I must admit the search condition diagram is quite confusing me.
alter table ExampleTable
    add (new_column varchar(20) default 'value1',
         constraint ckExampleTable check (new_column in ('value1', 'value2', 'value3')));