user: Question: What date has George Giffen as the home captain, and Sydney Cricket Ground as the venue?
Columns: ['Date', 'Home captain', 'Away captain', 'Venue', 'Result']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['14, 15, 17, 18, 19, 20 Dec 1894', 'Jack Blackham', 'Andrew Stoddart', 'Sydney Cricket Ground', 'ENG by 10 runs']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Home captain" = 'George Giffen' AND "Venue" = 'Sydney Cricket Ground';