user: Question: Which jockey had a group of G3?
Columns: ['Result', 'Date', 'Race', 'Venue', 'Group', 'Distance', 'Weight (kg)', 'Time', 'Jockey', 'Winner/2nd']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'real', 'text', 'text', 'text']
Sample row: ['Won', '18 Aug 2001', 'Warwick Stakes', 'Warwick Farm', 'G2', '1300 m', 49.5, '1:17.30', 'D. McLellan', '2nd - Diamond Dane']
SQL:

assistant: SELECT "Jockey" FROM "Table" WHERE "Group" = 'G3';