user: Question: What is the total of crowd at Venue of MCG?
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', '7.10 (52)', 'Richmond', '13.16 (94)', 'Western Oval', 30000.0, '16 May 1931']
SQL:

assistant: SELECT SUM("Crowd") FROM "Table" WHERE "Venue" = 'MCG';