create table parent(
id int unique key
) engine innodb;
create table child(
parent_id int,
foreign key(parent_id) references parent(id)
on delete restrict
on update restrict
) engine innodb with system versioning;
insert into parent values(1);
insert into child values(1);
delete from parent where id = 1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
delete from child where parent_id = 1;
delete from parent where id = 1;
insert into parent values(1);
insert into child values(1);
update parent set id=id+1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
delete from child;
update parent set id=id+1;
select * from child for system_time from timestamp '1-1-1' to timestamp now(6);
parent_id
1
1
drop table child;
drop table parent;
create table parent(
id int(10) unsigned unique key
) engine innodb;
create table child(
parent_id int(10) unsigned primary key,
foreign key(parent_id) references parent(id)
) engine innodb with system versioning;
insert into parent values(1);
insert into child values(1);
delete from parent where id = 1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
drop table child;
drop table parent;
create table parent(
id int unique key
) engine innodb;
create table child(
parent_id int,
foreign key(parent_id) references parent(id)
on delete cascade
on update cascade
) engine innodb with system versioning;
insert into parent values(1);
insert into child values(1);
delete from parent where id = 1;
select * from child;
parent_id
select * from child for system_time from timestamp '1-1-1' to timestamp now(6);
parent_id
1
insert into parent values(1);
insert into child values(1);
update parent set id=id+1;
select * from child;
parent_id
2
select * from child for system_time from timestamp '1-1-1' to timestamp now(6);
parent_id
1
2
drop table child;
drop table parent;
create table parent(
id int unique key
) engine innodb;
create table child(
parent_id int,
foreign key(parent_id) references parent(id)
on delete set null
on update set null
) engine innodb with system versioning;
insert into parent values(1);
insert into child values(1);
delete from child;
insert into child values(1);
delete from parent where id = 1;
select * from child;
parent_id
NULL
select * from child for system_time from timestamp '1-1-1' to timestamp now(6);
parent_id
1
NULL
delete from child;
insert into parent values(1);
insert into child values(1);
update parent set id=id+1;
select * from child;
parent_id
NULL
select * from child for system_time from timestamp '1-1-1' to timestamp now(6);
parent_id
1
NULL
NULL
drop table child;
drop table parent;
create or replace table parent(
id int unique key
) engine innodb with system versioning;
create or replace table child(
parent_id int,
foreign key(parent_id) references parent(id)
) engine innodb;
insert into parent values(1);
insert into child values(1);
delete from parent;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
update parent set id=2;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
delete from child;
delete from parent;
insert into child values(1);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
insert into parent values(1);
insert into child values(1);
delete from parent;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
update parent set id=2;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`))
drop table child;
drop table parent;