what is the earliest began when the court surface is clay in hamburg?
CREATE TABLE table_8963 (
    "Tournament" text,
    "Country" text,
    "Location" text,
    "Began" real,
    "Court surface" text
)
SELECT MIN("Began") FROM table_8963 WHERE "Court surface" = 'clay' AND "Location" = 'hamburg'
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 began when the court surface is clay in hamburg? ### Input: CREATE TABLE table_8963 (
    "Tournament" text,
    "Country" text,
    "Location" text,
    "Began" real,
    "Court surface" text
) ### Response: SELECT MIN("Began") FROM table_8963 WHERE "Court surface" = 'clay' AND "Location" = 'hamburg'