MySQLの外部キー挿入
3313 ワード
:
:alter table add constraint FK_ID foreign key( ) REFERENCES ( );
: alter table tb_active add constraint FK_ID foreign key(user_id) REFERENCES tb_user(id)
//FK_ID
/*
CREATE TABLE `tb_active` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`title` varchar(100) CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL,
`content` text CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL,
`user_id` int(11) NOT NULL,
PRIMARY KEY (`id`),
KEY `user_id` (`user_id`),
KEY `user_id_2` (`user_id`),
CONSTRAINT `FK_ID` FOREIGN KEY (`user_id`) REFERENCES `tb_user` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
*/
: ALTER TABLE table-name DROP FOREIGN KEY key-id;
: ALTER TABLE `tb_active` DROP FOREIGN KEY `FK_ID`
:
, , REFERENCES ? ?
, , ,MYSQL FOREIGN KEY...REFERENCES ON
DELETE
ON UPDATE ,
CASCADE
SET NULL , NULL ( NOT NULL )
RESTRICT , , ( , )
NO ACTION
, ON UPDATE ON
DELETE
, MYSQL , , ,
: ON
DELETE
CASCADE , , , , .
alter table locstock add foreign key locstock_ibfk2(stockid) references product(stockid)
locstock , locstock_ibfk2 , product ,
alter table locstock drop foreign key locstock_ibfk2
show create table locstock
[CONSTRAINT symbol] FOREIGN KEY [id] (index_col_name, ...)
REFERENCES tbl_name (index_col_name, ...)
[ON
DELETE
{RESTRICT | CASCADE | SET NULL | NO ACTION}]
[ON UPDATE {RESTRICT | CASCADE | SET NULL | NO ACTION}]
tables InnoDB , 。
· , , 。 , 。
· , , 。
· 。 BLOB TEXT , 。
· CONSTRAINTsymbol , 。 ,InnoDB 。