生产异常 Cause: com.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: Lock wait timeout exceed_nested exception is com.mysql.cj.jdbc.exceptions.m

1、程序中报错日志：

Cause: com.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: 
Lock wait timeout exceeded; try restarting transaction;
 Lock wait timeout exceeded; try restarting transaction; 
nested exception is com.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: 
Lock wait timeout exceeded; try restarting transaction

2、查看未提交事务：
 
select * from  information_schema.INNODB_TRX;
 
SELECT 
    a.id,a.user,a.host,b.trx_started,b.trx_query 
FROM information_schema.processlist a RIGHT OUTER JOIN information_schema.innodb_trx b
ON a.id = b.trx_mysql_thread_id;

3、手动执行该update语句，失败，等待锁超时：

update orders set *** where id='79302e18a8e848ccb2323c48ca4ca349';
 
update orders set *** where id='aeff09dbbc1a4668bf959f675d536ece';

4、由于是生产，急需处理业务数据，所以临时解决方案，是先kill 掉，未能提交事务的线程，

kill  trx_mysql_thread_id（上图中的trx_mysql_thread_id是10， 所以 执行  kill  10）

目前的解决方案，就是手动kill掉长期挂起，未提交的事务。