CREATE TABLE $TTT ( name varchar(50) CHARACTER SET ascii NOT NULL, value bigint UNSIGNED NOT NULL, PRIMARY KEY (name) ) ENGINE=InnoDB;

insert into $TTT values ('a', 100), ('b', 100);

connA: start transaction;

connB: start transaction;

connA: update $TTT set value = 703 where name = 'b';

connB: update $TTT set value = 795 where name != 'b';
# result is blocked by update on connA, but that is not the issue

connA: update $TTT set value = 944 where name != 'b';
# deadlock is detected correctly
# ERROR 1213 (40001): Deadlock found when trying to get lock; try restarting transaction
# note: connB outputs result

connA: select @@in_transaction;
# here we read "0", ie. transaction is terminated/rolled back

connA: update $TTT set value = 646;
# result is blocked by update on connB, but that is not the issue

connB: commit;
# note: connA outputs result

connA: select @@in_transaction;
# here we read "1" <-- here is the problem, transaction was started without a command!