MySQL Bugs: #21495: Alter table from x engine to ndb and back can cause issue with drop DB

Bug #21495	Alter table from x engine to ndb and back can cause issue with drop DB
Submitted:	7 Aug 2006 22:28	Modified:	6 Dec 2006 9:49
Reporter:	Jonathan Miller	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Cluster: Cluster (NDB) storage engine	Severity:	S3 (Non-critical)
Version:	5.1.12	OS:	Linux (Linux)
Assigned to:	Martin Skold	CPU Architecture:	Any

Description:
From Customer
The customer starts with a MyISAM table and alters it to NDB. Now all the mysqlds see the table. (This was part of pit fall number one that was documented in MySQL Bugs: #21378: Alter table from X storage engine to NDB could cause data loss)

Pifall No. 3:
Let's go back to our first mysqld and change our NDB table back to MyISAM.  SHOW TABLES on this node shows us one single MyISAM table, as expected.  This table has also disappeared on all the other mysqlds:

mysql> show tables;
Empty set (0.00 sec)

...which is also somewhat expected.  However, if I issue "DROP DATABASE ndbtest" on the first mysqld, all the other SQL Nodes will also drop their ndbtest database as well, even though there are no NDB tables in them, even if there were other non-NDB tables in those databases.

How to repeat:
See above

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/15339

ChangeSet@1.2322, 2006-11-15 11:13:49+01:00, mskold@mysql.com +6 -0
  bug #21495  Alter table from x engine to ndb and back can cause issue with drop DB:disable distributed drop database if a database contains local tables

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/15343

ChangeSet@1.2323, 2006-11-15 11:38:22+01:00, mskold@mysql.com +1 -0
  bug #21495  Alter table from x engine to ndb and back can cause issue with drop DB:added error printout to log

Thank you for your bug report. This issue has been committed to our source repository of that product and will be incorporated into the next release.

If necessary, you can access the source repository and build the latest available version, including the bug fix. More information about accessing the source trees is available at

    http://dev.mysql.com/doc/en/installing-source.html

Documented bugfix in 5.1.14 changelog.