mysql 开发指南

1.创建索引

create index PENALTIES_AMOUNT on penalties(amount);

删除： drop index  PENALTIES_AMOUNT;

2.创建索引

create view  number_sets (matchno,difference) as select matchno,abs(won-lost) from matches;

删除： drop view  number_sets;

使用方法:
select * from number_sets;

3.对用户限制在某个表操作
 grant select ,update on players  to dinnery