human
Considering the provided database schema and associated query, produce SQL code to retrieve the answer to the query. 
###Database Schema: Position, Sail number, Yacht, State/country, Yacht type, LOA (Metres), Skipper, Corrected time d:hh:mm:ss
###Question: What are all sail numbers for the yacht Yendys?
gpt
SELECT Sail number FROM table WHERE Yacht = Yendys