what's the earliest year that the wimbledon opponent was zheng jie?
CREATE TABLE table_name_50 (year INTEGER, event VARCHAR, opponent VARCHAR)
SELECT MIN(year) FROM table_name_50 WHERE event = "wimbledon" AND opponent = "zheng jie"
### Context: CREATE TABLE table_name_50 (year INTEGER, event VARCHAR, opponent VARCHAR) ### Question: what's the earliest year that the wimbledon opponent was zheng jie? ### Answer: SELECT MIN(year) FROM table_name_50 WHERE event = "wimbledon" AND opponent = "zheng jie"