Which number of Years has a Venue of old trafford, and an Opposition of yorkshire?
CREATE TABLE table_name_30 (
    year VARCHAR,
    venue VARCHAR,
    opposition VARCHAR
)
SELECT COUNT(year) FROM table_name_30 WHERE venue = "old trafford" AND opposition = "yorkshire"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: Which number of Years has a Venue of old trafford, and an Opposition of yorkshire? ### Input: CREATE TABLE table_name_30 (
    year VARCHAR,
    venue VARCHAR,
    opposition VARCHAR
) ### Response: SELECT COUNT(year) FROM table_name_30 WHERE venue = "old trafford" AND opposition = "yorkshire"