Which championship has Roger Federer as an opponent on a clay surface in a year earlier than 2007?
CREATE TABLE table_name_36 (championship VARCHAR, year VARCHAR, opponent VARCHAR, surface VARCHAR)
SELECT championship FROM table_name_36 WHERE opponent = "roger federer" AND surface = "clay" AND year < 2007
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_name_36 (championship VARCHAR, year VARCHAR, opponent VARCHAR, surface VARCHAR) Question: Which championship has Roger Federer as an opponent on a clay surface in a year earlier than 2007? [/INST] SELECT championship FROM table_name_36 WHERE opponent = "roger federer" AND surface = "clay" AND year < 2007 </s>