user: Question: If Collingwood was the Home team, what Date did they play?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Essendon', '20.9 (129)', 'South Melbourne', '19.19 (133)', 'Windy Hill', 17471.0, '19 July 1980']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Home team" = 'Collingwood';