config root man

CREATE TABLE parent (
id INT NOT NULL AUTO_INCREMENT,
bogus_column char(32),
PRIMARY KEY (id)
) ENGINE=ndb;
CREATE TABLE child (
id INT NOT NULL AUTO_INCREMENT,
parent_id INT NOT NULL,
bogus_column char(32),
PRIMARY KEY (id),
KEY (parent_id)
) ENGINE=ndb;
alter table child add constraint fkname foreign key (parent_id) references parent (id) on update restrict on delete restrict;
INSERT INTO parent (bogus_column)
VALUES ('aaa'), ('bbb'), ('ccc'), ('ddd'), ('eee');
INSERT INTO child (parent_id,bogus_column) VALUES
(1, 'aaa'), (2,'bbb'), (3, 'ccc'),
(4, 'ddd'), (5, 'eee');
START TRANSACTION;
START TRANSACTION;
UPDATE child SET parent_id = 5 WHERE parent_id = 4;
UPDATE parent SET bogus_column = 'new!' WHERE id = 4;
UPDATE parent SET bogus_column = 'new!' WHERE id = 5;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
rollback;
rollback;
alter table child drop foreign key fkname;
alter table child add constraint fkname foreign key (parent_id) references parent (id);
START TRANSACTION;
START TRANSACTION;
UPDATE child SET parent_id = 5 WHERE parent_id = 4;
UPDATE parent SET bogus_column = 'new!' WHERE id = 4;
UPDATE parent SET bogus_column = 'new!' WHERE id = 5;
commit;
commit;
drop table child, parent;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
ref_id int(11) default NULL,
PRIMARY KEY  (id),
KEY ref_id (ref_id),
CONSTRAINT ref_id FOREIGN KEY (ref_id) REFERENCES t1 (id)
) ENGINE=ndb;
INSERT INTO t1 VALUES (1, 1);
DELETE FROM t1 WHERE id = 1;
drop table t1;