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create or replace table a (
cola int(10) primary key,
v_cola int(10) as (cola mod 10) virtual,
p_cola int(10) as (cola mod 10) persistent
) engine=innodb;
create index v_cola on a (v_cola);
create index p_cola on a (p_cola);
create or replace table b(
cola int(10),
v_cola int(10),
p_cola int(10),
c_cola int(10) as (cola + 2) virtual
) engine=innodb;
alter table b add constraint `p_cola_fk`
foreign key (p_cola) references a (p_cola)
on delete restrict
on update restrict;
show warnings;
Level Code Message
show create table b;
Table Create Table
b CREATE TABLE `b` (
`cola` int(10) DEFAULT NULL,
`v_cola` int(10) DEFAULT NULL,
`p_cola` int(10) DEFAULT NULL,
`c_cola` int(10) GENERATED ALWAYS AS (`cola` + 2) VIRTUAL,
KEY `p_cola_fk` (`p_cola`),
CONSTRAINT `p_cola_fk` FOREIGN KEY (`p_cola`) REFERENCES `a` (`p_cola`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
alter table b add constraint `v_cola_fk`
foreign key (v_cola) references a (v_cola)
on delete restrict
on update restrict;
show warnings;
Level Code Message
show create table b;
Table Create Table
b CREATE TABLE `b` (
`cola` int(10) DEFAULT NULL,
`v_cola` int(10) DEFAULT NULL,
`p_cola` int(10) DEFAULT NULL,
`c_cola` int(10) GENERATED ALWAYS AS (`cola` + 2) VIRTUAL,
KEY `p_cola_fk` (`p_cola`),
KEY `v_cola_fk` (`v_cola`),
CONSTRAINT `p_cola_fk` FOREIGN KEY (`p_cola`) REFERENCES `a` (`p_cola`),
CONSTRAINT `v_cola_fk` FOREIGN KEY (`v_cola`) REFERENCES `a` (`v_cola`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
alter table b add constraint `c_cola_fk`
foreign key (c_cola) references a (cola)
on delete restrict
on update restrict;
show warnings;
Level Code Message
show create table b;
Table Create Table
b CREATE TABLE `b` (
`cola` int(10) DEFAULT NULL,
`v_cola` int(10) DEFAULT NULL,
`p_cola` int(10) DEFAULT NULL,
`c_cola` int(10) GENERATED ALWAYS AS (`cola` + 2) VIRTUAL,
KEY `p_cola_fk` (`p_cola`),
KEY `v_cola_fk` (`v_cola`),
KEY `c_cola_fk` (`c_cola`),
CONSTRAINT `c_cola_fk` FOREIGN KEY (`c_cola`) REFERENCES `a` (`cola`),
CONSTRAINT `p_cola_fk` FOREIGN KEY (`p_cola`) REFERENCES `a` (`p_cola`),
CONSTRAINT `v_cola_fk` FOREIGN KEY (`v_cola`) REFERENCES `a` (`v_cola`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
insert into a(cola) values (12);
select * from a;
cola v_cola p_cola
12 2 2
insert into b(cola, v_cola, p_cola) values (10,2,2);
select * from b;
cola v_cola p_cola c_cola
10 2 2 12
insert into b(cola, v_cola, p_cola) values (10,1,1);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`b`, CONSTRAINT `p_cola_fk` FOREIGN KEY (`p_cola`) REFERENCES `a` (`p_cola`))
delete from a;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`b`, CONSTRAINT `c_cola_fk` FOREIGN KEY (`c_cola`) REFERENCES `a` (`cola`))
select * from a;
cola v_cola p_cola
12 2 2
select * from b;
cola v_cola p_cola c_cola
10 2 2 12
drop table b, a;
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