connection node_2;
connection node_1;
#
# test phase with cascading foreign key through 3 tables
#
connection node_1;
CREATE TABLE grandparent (
id INT NOT NULL PRIMARY KEY
) ENGINE=InnoDB;
CREATE TABLE parent (
id INT NOT NULL PRIMARY KEY,
grandparent_id INT,
FOREIGN KEY (grandparent_id)
REFERENCES grandparent(id)
ON DELETE CASCADE
) ENGINE=InnoDB;
CREATE TABLE child (
id INT NOT NULL PRIMARY KEY, 
parent_id INT,
FOREIGN KEY (parent_id) 
REFERENCES parent(id)
ON DELETE CASCADE
) ENGINE=InnoDB;
INSERT INTO grandparent VALUES (1),(2);
INSERT INTO parent VALUES (1,1), (2,2);
INSERT INTO child VALUES (1,1), (2,2);
connection node_2;
DELETE FROM grandparent WHERE id = 1;
SELECT * FROM grandparent;
id
2
SELECT * FROM parent;
id	grandparent_id
2	2
SELECT * FROM child;
id	parent_id
2	2
connection node_1;
SELECT * FROM grandparent;
id
2
SELECT * FROM parent;
id	grandparent_id
2	2
SELECT * FROM child;
id	parent_id
2	2
DROP TABLE child;
DROP TABLE parent;
DROP TABLE grandparent;

Scenario 2, testing PA applying with FK cascade delete

CREATE TABLE p1 (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE p2 (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p1_id) REFERENCES p1 (f1)
ON DELETE CASCADE,
CONSTRAINT fk_2 FOREIGN KEY (p2_id) REFERENCES p2 (f1)
ON DELETE CASCADE);
connection node_2;
set global wsrep_slave_threads=DEFAULT;
SELECT * FROM p1;
f1	f2
SELECT * FROM p2;
f1	f2
SELECT * FROM c;
f1	p1_id	p2_id	f2
connection node_1;
DROP TABLE c;
DROP TABLE p1,p2;

Scenario 4, testing PA applying with FK cascade delete on
more than one level

CREATE TABLE gp1 (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE gp2 (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE p1 (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_3 FOREIGN KEY (p1_id) REFERENCES gp1 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE p2 (f1 INTEGER PRIMARY KEY,p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_4 FOREIGN KEY (p1_id) REFERENCES gp2 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p1_id) REFERENCES p1 (f1)
ON DELETE CASCADE,
CONSTRAINT fk_2 FOREIGN KEY (p2_id) REFERENCES p2 (f1)
ON DELETE CASCADE) ENGINE=INNODB;
connection node_2;
set global wsrep_slave_threads=DEFAULT;
SELECT * FROM gp1;
f1	f2
SELECT * FROM gp2;
f1	f2
SELECT * FROM p1;
f1	p1_id	p2_id	f2
SELECT * FROM p2;
f1	p1_id	p2_id	f2
SELECT * FROM c;
f1	p1_id	p2_id	f2
connection node_1;
DROP TABLE c;
DROP TABLE p1,p2;
DROP TABLE gp1,gp2;

Scenario 3, testing PA applying with FK cascade delete on
more than one level in a diamond topology

CREATE TABLE ggp1 (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE gp1 (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_6 FOREIGN KEY (p1_id) REFERENCES ggp1 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE gp2 (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_5 FOREIGN KEY (p1_id) REFERENCES ggp1 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE p1 (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_3 FOREIGN KEY (p1_id) REFERENCES gp1 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE p2 (f1 INTEGER PRIMARY KEY,p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT pfk_4 FOREIGN KEY (p1_id) REFERENCES gp2 (f1)
ON DELETE CASCADE
) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p1_id INTEGER, p2_id INTEGER,
f2 INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p1_id) REFERENCES p1 (f1)
ON DELETE CASCADE,
CONSTRAINT fk_2 FOREIGN KEY (p2_id) REFERENCES p2 (f1)
ON DELETE CASCADE) ENGINE=INNODB;
connection node_2;
set global wsrep_slave_threads=DEFAULT;
SELECT * FROM ggp1;
f1	f2
SELECT * FROM gp2;
f1	p1_id	p2_id	f2
SELECT * FROM gp1;
f1	p1_id	p2_id	f2
SELECT * FROM p1;
f1	p1_id	p2_id	f2
SELECT * FROM p2;
f1	p1_id	p2_id	f2
SELECT * FROM c;
f1	p1_id	p2_id	f2
connection node_1;
DROP TABLE c;
DROP TABLE p1,p2;
DROP TABLE gp1,gp2;
DROP TABLE ggp1;