How many years was the opponent petr korda?
CREATE TABLE table_name_21 (year VARCHAR, opponent VARCHAR)
SELECT COUNT(year) FROM table_name_21 WHERE opponent = "petr korda"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_name_21 (year VARCHAR, opponent VARCHAR) Question: How many years was the opponent petr korda? [/INST] SELECT COUNT(year) FROM table_name_21 WHERE opponent = "petr korda" </s>