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|
drop table if exists t1, t2;
CREATE TABLE t1
(
id INT PRIMARY KEY
) ENGINE=pbxt;
CREATE TABLE t2
(
v INT,
CONSTRAINT c1 FOREIGN KEY (v) REFERENCES t1(id)
) ENGINE=pbxt;
INSERT INTO t2 VALUES(2);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (Constraint: `c1`)
set foreign_key_checks = 0;
drop table t1;
set foreign_key_checks = 1;
INSERT INTO t2 VALUES(2);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (Referenced table `t1` not found)
drop table if exists parent, child, child_child;
CREATE TABLE parent (
id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=PBXT;
CREATE TABLE child (
id INT PRIMARY KEY,
parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id) REFERENCES parent(id) ON DELETE SET NULL ON UPDATE SET NULL
) ENGINE=PBXT;
insert parent values(1);
insert parent values(2);
insert child values(100, 1);
insert child values(200, 1);
insert child values(300, 2);
insert child values(400, 2);
update parent set id = 3 where id = 1;
select * from parent;
id
2
3
select * from child order by id;
id parent_id
100 NULL
200 NULL
300 2
400 2
delete from parent where id = 2;
select * from parent;
id
3
select * from child order by id;
id parent_id
100 NULL
200 NULL
300 NULL
400 NULL
set foreign_key_checks = 0;
drop table if exists parent, child, child_child;
set foreign_key_checks = 1;
CREATE TABLE parent (
id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=PBXT;
CREATE TABLE child (
id INT PRIMARY KEY,
parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id) REFERENCES parent(id) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=PBXT;
CREATE TABLE child_child (
id INT PRIMARY KEY,
child_id INT,
INDEX (child_id),
FOREIGN KEY (child_id) REFERENCES child(id) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=PBXT;
delete from parent;
delete from child;
delete from child_child;
insert parent values(1);
insert parent values(2);
insert child values(100, 1);
insert child values(200, 1);
insert child values(300, 2);
insert child values(400, 2);
insert child_child values(1000, 100);
insert child_child values(2000, 200);
insert child_child values(3000, 300);
insert child_child values(4000, 300);
insert child_child values(5000, 400);
select * from parent;
id
1
2
select * from child order by id;
id parent_id
100 1
200 1
300 2
400 2
select * from child_child;
id child_id
1000 100
2000 200
3000 300
4000 300
5000 400
update parent set id = 3 where id = 1;
select * from parent;
id
2
3
select * from child order by id;
id parent_id
100 3
200 3
300 2
400 2
delete from parent where id = 2;
select * from parent;
id
3
select * from child order by id;
id parent_id
100 3
200 3
select * from child_child;
id child_id
1000 100
2000 200
set foreign_key_checks = 0;
drop table if exists parent, child, child_child;
set foreign_key_checks = 1;
CREATE TABLE parent (
id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=PBXT;
CREATE TABLE child (
id INT,
parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id) REFERENCES parent(id)
) ENGINE=PBXT;
insert parent values(2);
insert parent values(1);
insert child values(100, 1);
insert child values(200, 1);
update parent set id = 3 where id = 1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (Constraint: `FOREIGN_1`)
delete from parent where id = 1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (Constraint: `FOREIGN_1`)
select * from parent;
id
1
2
select * from child order by id;
id parent_id
100 1
200 1
delete from child;
insert child values(100, 1);
insert child values(200, 1);
create index child_ind on child(id);
show create table child;
Table Create Table
child CREATE TABLE `child` (
`id` int(11) DEFAULT NULL,
`parent_id` int(11) DEFAULT NULL,
KEY `par_ind` (`parent_id`),
KEY `child_ind` (`id`),
CONSTRAINT `FOREIGN_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
drop index child_ind on child;
show create table child;
Table Create Table
child CREATE TABLE `child` (
`id` int(11) DEFAULT NULL,
`parent_id` int(11) DEFAULT NULL,
KEY `par_ind` (`parent_id`),
CONSTRAINT `FOREIGN_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
alter table parent add column c1 varchar(40);
insert child values(2000, 2);
select * from parent;
id c1
2 NULL
1 NULL
select * from child order by id;
id parent_id
100 1
200 1
2000 2
show create table parent;
Table Create Table
parent CREATE TABLE `parent` (
`id` int(11) NOT NULL,
`c1` varchar(40) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
alter table parent drop column c1;
select * from parent;
id
1
2
show create table parent;
Table Create Table
parent CREATE TABLE `parent` (
`id` int(11) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
alter table parent add column c1 int;
alter table parent drop column id;
insert child values(300, 1);
ERROR HY000: Cannot add foreign key constraint
alter table parent add column id int, add index (id);
select * from parent;
c1 id
NULL NULL
NULL NULL
insert child values(300, 1);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (Constraint: `FOREIGN_1`)
update parent set id = 1 where id is null limit 1;
update parent set id = 2 where id is null limit 1;
insert child values(300, 1);
select * from parent order by id;
c1 id
NULL 1
NULL 2
select * from child order by id;
id parent_id
100 1
200 1
300 1
2000 2
show create table parent;
Table Create Table
parent CREATE TABLE `parent` (
`c1` int(11) DEFAULT NULL,
`id` int(11) DEFAULT NULL,
KEY `id` (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
show create table child;
Table Create Table
child CREATE TABLE `child` (
`id` int(11) DEFAULT NULL,
`parent_id` int(11) DEFAULT NULL,
KEY `par_ind` (`parent_id`),
CONSTRAINT `FOREIGN_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
alter table child add column c1 varchar(40);
insert child values(400, 1, "asd");
select * from parent order by id;
c1 id
NULL 1
NULL 2
select * from child order by id;
id parent_id c1
100 1 NULL
200 1 NULL
300 1 NULL
400 1 asd
2000 2 NULL
alter table child drop key par_ind, drop column parent_id, add column parent_id int, add key par_ind (parent_id);
insert child (id, parent_id, c1) values(500, 1, "asd");
drop table if exists child, parent;
CREATE TABLE parent (
id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=PBXT;
CREATE TABLE child (
id INT,
parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id)
REFERENCES parent(id) ON DELETE CASCADE
) ENGINE=PBXT;
show create table parent;
Table Create Table
parent CREATE TABLE `parent` (
`id` int(11) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=PBXT DEFAULT CHARSET=latin1
show create table child;
Table Create Table
child CREATE TABLE `child` (
`id` int(11) DEFAULT NULL,
`parent_id` int(11) DEFAULT NULL,
KEY `par_ind` (`parent_id`),
CONSTRAINT `FOREIGN_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`) ON DELETE CASCADE
) ENGINE=PBXT DEFAULT CHARSET=latin1
insert parent values(1);
insert child values(100, 1);
insert child values(102, 2);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (Constraint: `FOREIGN_1`)
set foreign_key_checks = 0;
drop table if exists parent, child;
set foreign_key_checks = 1;
CREATE TABLE parent (
id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=PBXT;
CREATE TABLE child (
id INT,
parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id)
REFERENCES parent(glump) ON DELETE CASCADE
) ENGINE=PBXT;
insert parent values(1);
insert child values(100, 1);
ERROR HY000: Cannot add foreign key constraint
drop table if exists test1;
CREATE TABLE test1 (
id INT NOT NULL,
c1 varchar(30),
PRIMARY KEY (id)
) ENGINE=pbxt;
insert test1 values(1, "asd");
insert test1 values(2, "qwer");
alter table test1 drop column id, drop primary key, add column id int;
show create table test1;
Table Create Table
test1 CREATE TABLE `test1` (
`c1` varchar(30) DEFAULT NULL,
`id` int(11) DEFAULT NULL
) ENGINE=PBXT DEFAULT CHARSET=latin1
select * from test1;
c1 id
asd NULL
qwer NULL
drop table if exists `ΤΑΒΜΙΓΑ`, t2;
create table `ΤΑΒΜΙΓΑ` (
id int primary key
) engine=pbxt;
CREATE TABLE t2
(
ΠΟΜΕ int NOT NULL,
cc varchar(20),
foreign key (ΠΟΜΕ) references `ΤΑΒΜΙΓΑ` (id),
index (ΠΟΜΕ)
) engine=pbxt;
insert `ΤΑΒΜΙΓΑ` values (1);
insert t2 values (1, "asd");
select * from `ΤΑΒΜΙΓΑ`;
id
1
set foreign_key_checks = 0;
drop table if exists test1, parent, child, child_child, `ΤΑΒΜΙΓΑ`, t2;
set foreign_key_checks = 1;
SET CHARACTER SET koi8r;
SET NAMES binary;
create table `ΡΠ΅ΡΡ` (
id int primary key
) engine=pbxt;
CREATE TABLE `2ΡΠ΅ΡΡ` (
`ΡΠ΅ΡΡ` int,
foreign key (`ΡΠ΅ΡΡ`) references `ΡΠ΅ΡΡ`(id),
index (`ΡΠ΅ΡΡ`)
) engine=pbxt;
select * from `ΡΠ΅ΡΡ`;
id
select * from `2ΡΠ΅ΡΡ`;
ΡΠ΅ΡΡ
set foreign_key_checks = 0;
drop table if exists `ΡΠ΅ΡΡ`, `2ΡΠ΅ΡΡ`;
set foreign_key_checks = 1;
drop table if exists t2, t1;
set foreign_key_checks = 1;
CREATE TABLE t2 (s1 INT DEFAULT NULL, FOREIGN KEY (s1) REFERENCES t1 (s1));
ERROR HY000: Can't create table 'test.t2' (errno: 151)
set foreign_key_checks = 0;
CREATE TABLE t2 (s1 INT DEFAULT NULL, FOREIGN KEY (s1) REFERENCES t1 (s1));
set foreign_key_checks = 1;
insert into t2 values (1);
ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (Referenced table `t1` not found)
set foreign_key_checks = 0;
insert into t2 values (1);
CREATE TABLE t1 (s1 INT PRIMARY KEY);
set foreign_key_checks = 1;
DROP TABLE t1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
set foreign_key_checks = 0;
DROP TABLE t1;
DROP TABLE t2;
set foreign_key_checks = 1;
CREATE TABLE t1 (s1 INT DEFAULT NULL, s2 INT DEFAULT NULL, s3 INT DEFAULT NULL, s4 INT DEFAULT NULL,
INDEX (s1), INDEX (s2), INDEX (s3), INDEX (s4),
FOREIGN KEY (s1) REFERENCES t1 (s2),
FOREIGN KEY (s2) REFERENCES t1 (s3),
FOREIGN KEY (s3) REFERENCES t1 (s4));
DROP TABLE t1;
CREATE TABLE t1 (s1 INT DEFAULT NULL, s2 INT DEFAULT NULL, s3 INT DEFAULT NULL, s4 INT DEFAULT NULL,
INDEX (s1), INDEX (s2), INDEX (s3), INDEX (s4),
FOREIGN KEY (s1) REFERENCES t1 (s2),
FOREIGN KEY (s2) REFERENCES t1 (s3),
FOREIGN KEY (s3) REFERENCES t1 (s4));
CREATE TABLE t2 (s1 INT DEFAULT NULL, FOREIGN KEY (s1) REFERENCES t1 (s1));
DROP TABLE t1;
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
DROP TABLE t2;
DROP TABLE t1;
CREATE TABLE t2 (s1 INT, INDEX (s1));
set foreign_key_checks = 0;
ALTER TABLE t2 ADD FOREIGN KEY (s1) REFERENCES t1 (s1);
DROP TABLE IF EXISTS t2, t1;
set foreign_key_checks = 1;
|
