CREATE DOMAIN state_code AS char(2)
DEFAULT '??'
CONSTRAINT valid_state_code
CHECK (value IN ('AL', 'AK', 'AZ', ...));
This applies to all tables each having a column named state_code.
There is no magic name logic involved. A domain is just a type with inherent constraints that are user definable. You make use of it like any other type.
Create table tbl (
column_name state_code not null
)
Values stored in column_name are now of type state_code and constrained to be one of the check constraint values.
David J.
