mysql建表语句key的含义CREATE TABLE `admin_role` (
`adminSet_id` varchar(32) NOT NULL,
`roleSet_id` varchar(32) NOT NULL,
PRIMARY KEY  (`adminSet_id`,`roleSet_id`),
KEY `FK9FC63FA6DAED032` (`adminSet_id`),
KEY `FK9FC63FA6C7B24C48` (`roleSet_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
跪求这个建表语句中关键字KEY的意思
CREATE TABLE `admin_role` (
`adminSet_id` varchar(32) NOT NULL,
`roleSet_id` varchar(32) NOT NULL,
PRIMARY KEY (`adminSet_id`,`roleSet_id`),
engine什么意思KEY `FK9FC63FA6DAED032` (`adminSet_id`),
KEY `FK9FC63FA6C7B24C48` (`roleSet_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
主键,两个列组合在⼀起,是唯⼀的,内建唯⼀性索引,并且不能为NULL
另外,两个Key定义相当于分别对这两列建⽴索引。