Question: Give the earliest year that featured Pi Hongyan on women's singles.
SQL: SELECT MIN("Year") FROM "2-12164707-1" WHERE "Women's singles" = 'Pi Hongyan';

Question: What's the first year that Guo Xin featured in women's singles?
SQL: SELECT MIN("Year") FROM "2-12164707-1" WHERE "Women's singles" = 'Guo Xin';