creating two fields that together are UNIQUE

[Agnar Renolen]

I want to create a table that stores records from different countries. Each record has a six-character identifier (id) that uniquely defines the record whithin ech country specified as two-character country code (country). For example, I can have multiple records in the database with the id='ABCDEF', but they must all have different country code.

Is it posible using mySQL to specify that two fields together form a unique pair,
such as:

CREATE TABLE MyTable (
country CHAR(2) NOT NULL,
id CHAR(6) NOT NULL,
...
UNIQUE(country,id)
);

Or is it other ways to ensure this constraint?