如何查看innodb_lock_wait_timeout的具体值？
SHOW VARIABLES LIKE 'innodb_lock_wait_timeout'
参数修改的范围有Session和Global，并且支持动态修改
set innodb_lock_wait_timeout=100;
set global innodb_lock_wait_timeout=100;
参考 https://ningyu1.github.io/site/post/75-mysql-lock-wait-timeout-exceeded/
