题解 | 显然GPT写的更完美

/* update titles_test
set to_date=NULL,from_date='2001-01-01'
where to_date='9999-01-01'; */ -- 自己写的

UPDATE titles_test
SET to_date = CASE 
    WHEN to_date = '9999-01-01' THEN NULL
    ELSE to_date
    END,
from_date = '2001-01-01'
WHERE to_date = '9999-01-01'; -- gpt写的