What is the earliest Date on a Surface of clay in a Championship in Linz, Austria?
CREATE TABLE table_name_15 (date INTEGER, surface VARCHAR, championship VARCHAR)
SELECT MIN(date) FROM table_name_15 WHERE surface = "clay" AND championship = "linz, austria"
### Context: CREATE TABLE table_name_15 (date INTEGER, surface VARCHAR, championship VARCHAR) ### Question: What is the earliest Date on a Surface of clay in a Championship in Linz, Austria? ### Answer: SELECT MIN(date) FROM table_name_15 WHERE surface = "clay" AND championship = "linz, austria"