MySQL 事务没有提交导致 锁等待 Lock wait timeout exceeded

java.lang.Exception:
### Error updating database.  Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
; SQL []; Lock wait timeout exceeded; try restarting transaction; nested exception is java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction

select * from information_schema.innodb_trx 之后找到了一个一直没有提交的只读事务，

kill 到了对应的线程后ok 了。