gap lock dead lock rock you

lock_empty.sh

#!/bin/sh
cat <<EOS | mysql -uroot
  CREATE DATABASE IF NOT EXISTS lock_test;
  USE lock_test;
  DROP TABLE IF EXISTS example;
  CREATE TABLE example (
    id bigint unsigned NOT NULL,
    name VARCHAR(10) NOT NULL,
    count int NOT NULL,
    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (id, name)
  ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=DYNAMIC;
EOS

cat <<EOS > query1.sql
  USE lock_test;
  INSERT INTO example SET id = 1, name = 'hoge', count = 0;
  INSERT INTO example SET id = 2, name = 'fuga', count = 0;

  BEGIN;
  \! echo 1: SELECT ... FOR UPDATE \(not exist\)
  SELECT * FROM example WHERE id = 10 AND name = 'foo' FOR UPDATE;
  \! echo 1: SELECT done

  DO SLEEP(2);

  \! echo 1: INSERT
  INSERT INTO example SET id = 10, name = 'foo', count = 1 ON DUPLICATE KEY UPDATE count = count + 1, updated_at = CURRENT_TIMESTAMP;
  \! echo 1: INSERT done

  DO SLEEP(2);

  COMMIT;
EOS

cat <<EOS > query2.sql
  USE lock_test;
  DO SLEEP(1);

  BEGIN;
  \! echo 2: SELECT ... FOR UPDATE \(not exist\)
  SELECT * FROM example WHERE id = 7 AND name = 'bar' FOR UPDATE;
  \! echo 2: SELECT done

  \! echo 2: INSERT
  INSERT INTO example SET id = 7, name = 'bar', count = 1 ON DUPLICATE KEY UPDATE count = count + 1, updated_at = CURRENT_TIMESTAMP;
  \! echo 2: INSERT done

  DO SLEEP(2);

  COMMIT;
EOS

mysql -uroot -t -e 'source ./query1.sql' &
mysql -uroot -t -e 'source ./query2.sql' &

wait
echo '====='
cat <<EOS | mysql -uroot -t
  USE lock_test;
  SELECT * FROM example;
EOS