user: Question: What is the date when the away team is Essendon?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Carlton', '21.19 (145)', 'Essendon', '14.12 (96)', 'Princes Park', 23948.0, '4 April 1970']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Away team" = 'Essendon';