针对如下表actor结构创建索引： CREATE TABLE IF NOT EXISTS actor ( actor_id smallint(5) NOT NULL PRIMARY KEY, first_name varchar(45) NOT NULL, last_name varchar(45) NOT NULL, last_update timestamp NOT NULL DEFAULT (datetime(‘now‘,‘localtime‘))) 对first_name创建唯一索引uniq_idx_firstname，对last_name创建普通索引idx_lastname
2、代码
CREATEUNIQUEINDEX uniq_idx_firstname ON actor(first_name);
CREATEINDEX idx_lastname ON actor(last_name);
