Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_19 (surface VARCHAR, outcome VARCHAR, date VARCHAR)
### Question:
What was the surface where the outcome was winner on 12 march 1989?
### Answer:
SELECT surface FROM table_name_19 WHERE outcome = "winner" AND date = "12 march 1989"