user: Question: What date was the game played at Lake Oval?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Footscray', '13.7 (85)', 'Melbourne', '6.12 (48)', 'Western Oval', 10441.0, '18 May 1968']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Venue" = 'Lake Oval';