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MDEV-12398 All cluster nodes stop due to a foreign key constraint fai…

…lure

Comment from Codership:-
To fix the problem, we changed the certification logic in galera to treat insert
on child table row as exclusive to prevent any operation on referenced
parent table row. At the same time, update and delete on
 child table row were demoted to "shared", which makes it possible to
update/delete referenced parent table row, but only in a later transaction.
 This change allows somewhat more concurrency for foreign key constrained
 transactions, but is still safe for correct certification end result.
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SachinSetiya committed Jun 22, 2017
1 parent 472c2d9 commit e333d8296480afc63962892f6c8e101dfcaa2686
@@ -0,0 +1,155 @@
CREATE TABLE p (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p_id INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p_id) REFERENCES p (f1)) ;
INSERT INTO p VALUES (1, 0);
INSERT INTO p VALUES (2, 0);
SET AUTOCOMMIT=ON;
START TRANSACTION;
DELETE FROM p WHERE f1 = 1;
SET SESSION wsrep_sync_wait = 0;
SET GLOBAL wsrep_provider_options = 'dbug=d,apply_monitor_slave_enter_sync';
INSERT INTO c VALUES (1, 1);
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'dbug=';
SET GLOBAL wsrep_provider_options = 'dbug=d,local_monitor_enter_sync';
COMMIT;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'signal=apply_monitor_slave_enter_sync';
SET GLOBAL wsrep_provider_options = 'signal=local_monitor_enter_sync';
SET GLOBAL wsrep_provider_options = 'dbug=';
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
SELECT * FROM p;
f1 f2
1 0
2 0
SELECT * FROM c;
f1 p_id
1 1
DROP TABLE c;
DROP TABLE p;
CREATE TABLE p (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p_id INTEGER,
f2 INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p_id) REFERENCES p (f1)) ;
INSERT INTO p VALUES (1, 0);
INSERT INTO p VALUES (2, 0);
INSERT INTO c VALUES (1, 1, 0);
SET AUTOCOMMIT=ON;
START TRANSACTION;
UPDATE p SET f2 = 1 WHERE f1 = 1;
SET SESSION wsrep_sync_wait = 0;
SET GLOBAL wsrep_provider_options = 'dbug=d,apply_monitor_slave_enter_sync';
UPDATE c SET f2 = 1 WHERE f1 = 1;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'dbug=';
SET GLOBAL wsrep_provider_options = 'dbug=d,local_monitor_enter_sync';
COMMIT;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'signal=apply_monitor_slave_enter_sync';
SET GLOBAL wsrep_provider_options = 'signal=local_monitor_enter_sync';
SET GLOBAL wsrep_provider_options = 'dbug=';
SELECT * FROM p;
f1 f2
1 1
2 0
SELECT * FROM c;
f1 p_id f2
1 1 1
DROP TABLE c;
DROP TABLE p;
CREATE TABLE p (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p_id INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p_id) REFERENCES p (f1)) ;
INSERT INTO p VALUES (1, 0);
INSERT INTO p VALUES (2, 0);
INSERT INTO c VALUES (1, 1);
SET AUTOCOMMIT=ON;
START TRANSACTION;
UPDATE p SET f2 = 1 WHERE f1 = 1;
SET SESSION wsrep_sync_wait = 0;
SET GLOBAL wsrep_provider_options = 'dbug=d,apply_monitor_slave_enter_sync';
DELETE FROM c WHERE f1 = 1;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'dbug=';
SET GLOBAL wsrep_provider_options = 'dbug=d,local_monitor_enter_sync';
COMMIT;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'signal=apply_monitor_slave_enter_sync';
SET GLOBAL wsrep_provider_options = 'signal=local_monitor_enter_sync';
SET GLOBAL wsrep_provider_options = 'dbug=';
SELECT * FROM p;
f1 f2
1 1
2 0
SELECT * FROM c;
f1 p_id
DROP TABLE c;
DROP TABLE p;
CREATE TABLE p (f1 INTEGER PRIMARY KEY, f2 INTEGER UNIQUE KEY) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p_id INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p_id) REFERENCES p (f2)) ;
INSERT INTO p VALUES (1, 0);
SET AUTOCOMMIT=ON;
START TRANSACTION;
UPDATE p SET f2 = 1 WHERE f1 = 1;
SET SESSION wsrep_sync_wait = 0;
SET GLOBAL wsrep_provider_options = 'dbug=d,apply_monitor_slave_enter_sync';
INSERT INTO c VALUES (1, 0);;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'dbug=';
SET GLOBAL wsrep_provider_options = 'dbug=d,local_monitor_enter_sync';
COMMIT;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'signal=apply_monitor_slave_enter_sync';
SET GLOBAL wsrep_provider_options = 'signal=local_monitor_enter_sync';
SET GLOBAL wsrep_provider_options = 'dbug=';
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
SELECT * FROM p;
f1 f2
1 0
SELECT * FROM c;
f1 p_id
1 0
DROP TABLE c;
DROP TABLE p;
CREATE TABLE p (f1 INTEGER PRIMARY KEY, f2 INTEGER) ENGINE=INNODB;
CREATE TABLE c (f1 INTEGER PRIMARY KEY, p_id INTEGER, f2 INTEGER,
CONSTRAINT fk_1 FOREIGN KEY (p_id) REFERENCES p (f1)
ON DELETE CASCADE) ;
INSERT INTO p VALUES (1, 0);
INSERT INTO p VALUES (2, 0);
INSERT INTO c VALUES (1, 1, 0);
SET AUTOCOMMIT=ON;
START TRANSACTION;
DELETE FROM p WHERE f1 = 1;
SET SESSION wsrep_sync_wait = 0;
SET GLOBAL wsrep_provider_options = 'dbug=d,apply_monitor_slave_enter_sync';
UPDATE c SET f2 = 1 WHERE f1 = 1;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'dbug=';
SET GLOBAL wsrep_provider_options = 'dbug=d,local_monitor_enter_sync';
COMMIT;
SET SESSION wsrep_on = 0;
SET SESSION wsrep_on = 1;
SET GLOBAL wsrep_provider_options = 'signal=apply_monitor_slave_enter_sync';
SET GLOBAL wsrep_provider_options = 'signal=local_monitor_enter_sync';
SET GLOBAL wsrep_provider_options = 'dbug=';
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
SELECT * FROM p;
f1 f2
1 0
2 0
SELECT * FROM c;
f1 p_id f2
1 1 1
DROP TABLE c;
DROP TABLE p;
@@ -0,0 +1,75 @@
#
# This file should be included from tests for MW-369 to run concurrent
# transaction from node_1 with autocommit query from node_2.
#
# The parameters:
# * $mw_369_parent_query - the parent query to be run inside transaction
# * $mw_369_child_query - the child query
#
# The operations are the following:
#
# node_1:
# START TRANSACTION;
# $mw_369_parent_query
# node_2
# $mw_369_child_query - will be blocked on node_1 in apply monitor
# node_1:
# COMMIT; - will be blocked on node_1 in local monitor
#
# The $mw_369_child_query is always expected to succeed. The caller is
# responsible for checking if the final COMMIT on connection node_1
# succeeds.
#

--connection node_1
SET AUTOCOMMIT=ON;
START TRANSACTION;

--eval $mw_369_parent_query

#
# Block the $mw_369_child_query from node_2
#
# --connect node_1a, 127.0.0.1, root, , test, $NODE_MYPORT_1
--connection node_1a
SET SESSION wsrep_sync_wait = 0;
--let $galera_sync_point = apply_monitor_slave_enter_sync
--source include/galera_set_sync_point.inc

#
# insert client row, which will make it impossible to replay the
# delete on parent
#
--connection node_2
--eval $mw_369_child_query

#
# Wait until $mw_369_child_query from node_2 reaches the sync point and
# block the 'COMMIT' from node_1 before it certifies.
#
--connection node_1a
--source include/galera_wait_sync_point.inc
--source include/galera_clear_sync_point.inc

--let $galera_sync_point = local_monitor_enter_sync
--source include/galera_set_sync_point.inc

--connection node_1
--send COMMIT

#
# Wait until both sync points have been reached
#
--connection node_1a
--let $galera_sync_point = apply_monitor_slave_enter_sync local_monitor_enter_sync
--source include/galera_wait_sync_point.inc

#
# both threads are now parked in sync points, signal them to continue
#
--let $galera_sync_point = apply_monitor_slave_enter_sync
--source include/galera_signal_sync_point.inc

--let $galera_sync_point = local_monitor_enter_sync
--source include/galera_signal_sync_point.inc
--source include/galera_clear_sync_point.inc

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