user: Question: What is the date for Hydra Head Records with a CD format?
Columns: ['Country', 'Date', 'Label', 'Format', 'Catalogue #']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['United States', 'December 8, 2004', 'Hydra Head Records', 'CD', 'HH666-79']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Label" = 'Hydra Head Records' AND "Format" = 'CD';