Sorry Shie, but country is really not an issue.  In dealing with companies, their holidays are different between them even when they are in the same country.  If you want to do it correctly, the Date table would be independent of the country/company.  The country/company would be it's own table.  The holiday name would be it's own table.  And, finally, the intersection table of the holiday, company/country, and the date itself.  Using a unique index on the combination and a surrogate key (identity column) for the primary key.  Enterprise solution VS not.