mysql关于外键设置

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3.鍏充簬澶栭敭

create table roominfo

(

聽 聽r_code 聽 聽 聽 聽 聽 聽 聽 char(4) not null,

聽 聽r_type 聽 聽 聽 聽 聽 聽 聽 char(10) not null,

聽 聽r_price 聽 聽 聽 聽 聽 聽 聽float(8,2) not null,

聽 聽r_iflive 聽 聽 聽 聽 聽 聽 bool not null,

聽 聽r_floor 聽 聽 聽 聽 聽 聽 聽int not null,

聽 聽r_notes 聽 聽 聽 聽 聽 聽 聽longtext,

聽 聽primary key (r_code, r_type)

) ENGINE=InnoDB DEFAULT CHARSET=gbk;

create table orderinfo

(

聽 聽od_code 聽 聽 聽 聽 聽 聽 聽char(15) not null,

聽 聽r_code 聽 聽 聽 聽 聽 聽 聽 char(4),

聽 聽r_type 聽 聽 聽 聽 聽 聽 聽 char(10),

聽 聽od_intime 聽 聽 聽 聽 聽 聽datetime not null,

聽 聽od_outtime 聽 聽 聽 聽 聽 datetime not null,

聽 聽od_pay 聽 聽 聽 聽 聽 聽 聽 float(8,2) not null,

聽 聽od_hphone 聽 聽 聽 聽 聽 聽char(11),

聽 聽od_notes 聽 聽 聽 聽 聽 聽 longtext,

聽 聽primary key (od_code)

) ENGINE=InnoDB DEFAULT CHARSET=gbk;

alter table orderinfo add constraint FK_Relationship_1 foreign key (r_code, r_type)

聽 聽 聽 references roominfo (r_code, r_type) on delete cascade on update cascade;

鍦╫rderinfo琛ㄤ腑璁剧疆澶栭敭r_code, r_type(灞炰簬琛╮oominfo)

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