The latest from the MySQL community

I’m quite pleased to announce that my pull request for Kubernetes which provides a 3-node Galera cluster for Kubernetes was merged last week. I gave a presentation at Percona Live 2015 in Santa Clara, CA back in April about this an had since modified it to use newer Kubernete’s functionality, particular now that Kubernetes services allow more than one port and Kubernetes requires several ports. Also, Skydns, which provides the ability to specify the name (vs. IP address) of each node’s service when building up the wsrep_cluster_address string as well as providing a cluster-wide service.

Tim St. Clair (Google) was quite through and very helpful in his review and the code and docuementation ended up being very complete. You can find it on Kubernetes’ source code repo:

…

Download MariaDB 5.5.46

Release Notes Changelog What is MariaDB 5.5?

MariaDB APT and YUM Repository Configuration Generator

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.46. This is a Stable (GA) release.

See the Release …

In the spirit of sharing war stories and avoiding others to do the same mistakes as I did, here are some sequences of commands that you should avoid to run on a MariaDB slave that is lagging and which is using the GTID protocol.  Remember, do not run those because...

So, those bad commands are the following:

"STOP SLAVE; START SLAVE UNTIL ...;", or "STOP SLAVE; START SLAVE;" (to remove an

Suppose you want to send a message from one SQL session to one or more other sessions, like "Hey, session#13, here is the latest figure for your calculation, please acknowledge". I'll say what Oracle and EnterpriseDB and DB2 do, then rate the various ways to implement something similar in MySQL and MariaDB, and finish with a demo of the procedure that we use, which is available as part of an open-source package.

The syntax was established by Oracle, with EnterpriseDB and IBM following suit. The details are in the Oracle 12c manual and the DB2 9.7 manual. The oversimplification is this:

  DBMS_PIPE.PACK_MESSAGE('message');
  SET status = DBMS_PIPE.SEND_MESSAGE('channel#1');
  SET status = …

This Log Buffer Edition covers some blog posts of Oracle, SQL Server and MySQL from this past week.

Oracle:

• Oracle Utilities Application Framework V4.3.0.1.0 includes a new help engine and changes to the organization of help.
• Very simple oracle package for HTTPS and HTTP.
• Tim spotted a problem with the PDB Logging Clause.
• How to Pass Arguments to OS Shell Script from Oracle Database.

SQL Server:

• How efficient is your covered …

mysql < quarto.sql

Example game play:

mysql> -- Start the game and pass the first piece in the lower nibble
mysql> CALL SetupGame(0x0A);
-----------------------------------------------------------------------+
| rules                                                                |
-----------------------------------------------------------------------+
| Quarto: 4 in a line (row, column, or long diagonal) with at least one bit in common wins.
CALL Play(move); -- high 4 bits are board position, low 4 bits are piece for next player
CALL PrintBoard(base); -- to display the board. Useful bases are 16 and 2. |
-----------------------------------------------------------------------+

+------------------------+
| instructions           |
+------------------------+
| Player 1, play piece A |
+------------------------+

mysql> CALL Play(0x00);
+---------+
| board   | …

I presented a talk at Percona Live Amsterdam a few weeks ago (simple recipes for your Galera cluster), and one of the topics was schema changes. I discussed the drawbacks and benefits of Total Order Isolation (TOI), Rolling Schema Upgrades (RSU) and pt-online-schema-change. One thing I forgot was …

The other day a colleague and friend of mine, Peter Boros, had a case where one of our clients had to track down the process shutting down MySQL. This blog is based on the discussion we had about that internally.

Our client wanted Peter to identify the culprit behind periodic shutdowns. This proved to be slightly more difficult than usual, for reasons that you might guess from the title of this blog.

Here is what Peter saw in the logs:

150928 15:15:33 [Note] /usr/sbin/mysqld: Normal shutdown
150928 15:15:36 [Note] Event Scheduler: Purging the queue. 0 events
150928 15:15:39 [Warning] /usr/sbin/mysqld: Forcing close of thread 411515  user: 'dashboard'
150928 15:15:40  InnoDB: Starting shutdown...
150928 15:15:59  InnoDB: Shutdown completed; log sequence number 4873840375
150928 15:16:00 [Note] /usr/sbin/mysqld: Shutdown …

Docker has been consuming my life in the last few weeks. I have half a dozen projects in progress that use containers in some fashion, including my Visualizing MySQL’s Performance Schema project.

Since I prefer to work from a Mac laptop, I have to utilize a Linux Virtual Machine (VM) which runs the Docker daemon. Luckily, Docker Machine makes this a very simple process.

However, interacting both with Docker and Docker Machine does introduce some additional commands that I would rather simplify for the repeatable use-cases I’ve come across. With BASH aliases, this is not a problem.

Is My Docker Environment Setup?

When …

Welcome to next topic dedicated to Group Replication plugin. Today’s topic is to get started with Group Replication. As you remember we set up our environment using MySQL Sandbox on Ubuntu 14.04 and also we have compiled plugin with MySQL 5.7.8-rc on Ubuntu 14.04. Please refer to this topics respectively:

1. MySQL Sandbox creating test environment
2. Compiling MySQL Group replication plugin

So we have already our 3 nodes of MySQL 5.7.8-rc + group replication plugin.
Before starting group replication. We need to play with Corosync. Here is very dedicated article to this -> …