题解 | #对first_name创建唯一索引uniq_idx_firstname#
对first_name创建唯一索引uniq_idx_firstname
http://www.nowcoder.com/practice/e1824daa0c49404aa602cf0cb34bdd75
CREATE INDEX idx_lastname ON actor(last_name);
CREATE UNIQUE INDEX uniq_idx_firstname ON actor(first_name);