connection node_2;
connection node_1;
connection node_1;
CREATE TABLE t1 (f1 ENUM('', 'one', 'two'), KEY (f1)) ENGINE=InnoDB;
INSERT INTO t1 VALUES ('');
INSERT INTO t1 VALUES ('one'), ('two');
INSERT IGNORE INTO t1 VALUES (0), (1), (2);
Warnings:
Warning	1265	Data truncated for column 'f1' at row 1
connection node_2;
SELECT COUNT(*) FROM t1;
COUNT(*)
6
SELECT COUNT(*) FROM t1 where f1 = '';
COUNT(*)
2
SELECT COUNT(*) FROM t1 where f1 = 'one';
COUNT(*)
2
DROP TABLE t1;
connection node_1;
CREATE TABLE t1 (f1 ENUM('', 'one', 'two', 'three', 'four') PRIMARY KEY) ENGINE=InnoDB;
INSERT INTO t1 VALUES (''), ('one'), ('two');
connection node_2;
SELECT COUNT(*) FROM t1;
COUNT(*)
3
SELECT COUNT(*) FROM t1 WHERE f1 = '';
COUNT(*)
1
connection node_1;
SET AUTOCOMMIT=OFF;
START TRANSACTION;
UPDATE t1 SET f1 = 'three' where f1 = '';
connection node_2;
SET AUTOCOMMIt=OFF;
START TRANSACTION;
UPDATE t1 SET f1 = 'four' where f1 = '';
connection node_1;
COMMIT;
connection node_2;
COMMIT;
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
connection node_1;
SELECT COUNT(*) FROM t1 WHERE f1 = 'three';
COUNT(*)
1
SELECT * FROM t1;
f1
one
two
three
DROP TABLE t1;