题解 | #将所有to_date为9999-01-01的全部更新为NULL#
将所有to_date为9999-01-01的全部更新为NULL
https://www.nowcoder.com/practice/859f28f43496404886a77600ea68ef59
update titles_test set to_date = null, from_date = '2001-01-01' where to_date = '9999-01-01'
update改多个用逗号, 不用and

