MySQL Bugs: #70161: unable to drop database

Bug #70161	unable to drop database
Submitted:	27 Aug 2013 12:16	Modified:	27 Sep 2013 13:21
Reporter:	rajnish kumar	Email Updates:
Status:	No Feedback	Impact on me:	None
Category:	MySQL Server	Severity:	S1 (Critical)
Version:	5.5.31	OS:	FreeBSD (ubuntu)
Assigned to:		CPU Architecture:	Any
Tags:	unable to drop database

Description:
	
Hi All,

when i am trying to drop a database ,its hangs up . when i see in processlist it show 

 | 20045 | root | localhost | NULL | Query | 4 | Waiting for table metadata lock | drop database dbname1

there is no foreign key in the database and there is no locking ,below are the details for the same:

mysql>
mysql> select * from INNODB_LOCKS ;
Empty set (0.00 sec)

mysql> select * from INNODB_LOCK_WAITS ;
Empty set (0.01 sec)

I don't knew why this happens , anyone have any ideas on the same .I am using

mysql : 5.5.31-0ubuntu0.12.04.1-log (Ubuntu)

How to repeat:
above mentioned :

Do you tried FLUSH TABLES ?. Try new version 5.5.33 also.

This is simply not a bug. One of the connections has an open transaction.  The transaction might not have touched any innodb table yet that is why you cannot see it in the innodb_trx table.  You must kill all the oldest connections until the problem disappears. 

http://dev.mysql.com/doc/refman/5.5/en/metadata-locking.html

You may want to set "lock_wait_timeout=60" to let queries error out instead of hanging forever.  Then find out which connection/application forgets to commit or sets autocommit=0 by accident.

No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".