mysql 主键只有一个,auto_increment 必须是键.
Error Code: 1075. Incorrect table definition;
there can be only one auto column and it must be defined as a key
auto column and is must be defined as a key (自增列,必须是一个键key)
create table `xx` (
`x_id` bigint unsigned not null auto_increment,
`xd_id`bigint unsigned not null comment '编号',
`x_com_id` varchar(20) not null default '' comment '',
key(x_id),
primary key(`x_com`,`xd_id`)
) engine=innodb default charset=utf8 comment 'xx';