When is the earliest year opened for huff hall that was established after 1974?
CREATE TABLE table_name_20 (
    opened INTEGER,
    venue VARCHAR,
    established VARCHAR
)
SELECT MIN(opened) FROM table_name_20 WHERE venue = "huff hall" AND established > 1974
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: When is the earliest year opened for huff hall that was established after 1974? ### Input: CREATE TABLE table_name_20 (
    opened INTEGER,
    venue VARCHAR,
    established VARCHAR
) ### Response: SELECT MIN(opened) FROM table_name_20 WHERE venue = "huff hall" AND established > 1974