What is the earliest year of disaffiliation of a CHCH-TV station, licensed in Hamilton, Ontario?
CREATE TABLE table_57501 (
    "City of license/market" text,
    "Station" text,
    "Channel TV ( RF )" text,
    "Year of affiliation" real,
    "Year of disaffiliation" real
)
SELECT MIN("Year of disaffiliation") FROM table_57501 WHERE "City of license/market" = 'hamilton, ontario'
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: What is the earliest year of disaffiliation of a CHCH-TV station, licensed in Hamilton, Ontario? ### Input: CREATE TABLE table_57501 (
    "City of license/market" text,
    "Station" text,
    "Channel TV ( RF )" text,
    "Year of affiliation" real,
    "Year of disaffiliation" real
) ### Response: SELECT MIN("Year of disaffiliation") FROM table_57501 WHERE "City of license/market" = 'hamilton, ontario'