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
mysql alter语句创建索引
1、alter table actor add unique uniq_idx_firstname(first_name);//唯一索引
2、alter table actor add index idx_lastname(last_name);//普通索引
3、create index index_name on tablename(col_name);//创建索引
4、alter table tablename add fulltext index_name(col_name);//创建全文索引
