user: ### NOW ANSWER:
Question: Who won Women's doubles when Zen Yaqiong won Women's singles?
Columns: ['Year', "Men's singles", "Women's singles", "Men's doubles", "Women's doubles", 'Mixed doubles']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1997.0, 'Thomas Wapp', 'Elena Nozdran', 'Mihail Popov Svetoslav Stojanov', 'Elena Nozdran Viktoria Evtuschenko', 'Valeriy Strelcov Elena Nozdran']
SQL:

assistant: SELECT "Women's doubles" FROM "Table" WHERE "Women's singles" = 'Zen Yaqiong';