Recently i updated to MySQL 5.6 and we were really excited about the very good overall performance. But beside a major bug concerning wrong results when running a SELECT that includes a HAVING based on a function (see http://bugs.mysql.com/bug.php?id=69638) we also noticed that from time to time the replication breaks with the following error:

Last_SQL_Errno: 1590
Last_SQL_Error: The incident LOST_EVENTS occured on the master. Message: error writing to the binary log

After some investigation it seemed like this happens if one modifies some user privileges, so we stumbled upon http://bugs.mysql.com/bug.php?id=68892.

Essentially the bug report says that if you use the wrong syntax for GRANT-statements the replication will break. So far, so bad. I told everyone who had the …

Catching up on our reading today, we saw a blog post from Chris Stevens, the multi-faceted VP of Engineering at Traxo, technology consultant, and Full Stack developer. In his post, he notes some of the impressive new database technologies he’s seeing lately in tech blogs and on the conference circuit.

Chris says that when it makes sense he advises his clients to look at non-relational datatstores, but for a number of reasons he works with MySQL wherever possible. Many of his clients looking to run globally distributed applications often need to distribute the database across more than one data center (geo-distribution) for fault tolerance and localized performance.

“Globally distributed applications often require localized performance,” he said in his post. “We can do some work loading front-end assets from CDN …

Dr Charles Bell and I recently presented a webinar on MySQL Utilities; there was a heavy focus on what you can acheive with them and how you should use them. In case you couldn’t attend or want to listen to some of the details again, the replay from that webinar is available here.

Abstract:

MySQL Utilities provide a collection of command-line utilities that are used for maintaining and administering MySQL databases, including:

• Admin Utilities (Clone, Copy, Compare, Diff, Export, Import)
• Replication Utilities (Setup, Configuration, Automated Slave Promotion)
• General Utilities (Disk Usage, Redundant Indexes, Search Meta Data)

Andrew Morgan and Chuck Bell will …

Multi master topologies blues

Tungsten Replicator is a powerful replication engine that, in addition to providing the same features as MySQL Replication, can also create several topologies, such as

• all-masters: every master in the deployment is a master, and all nodes are connected point-to-point, so that there is no single point of failure (SPOF).
• fan-in: Several masters can replicate into a single slave;
• star: It’s an all-masters topology, where one node acts as hub which simplifies the deployment at the price of creating a SPOF.

The real weakness of these topologies is that they don’t come together easily. Installation requires several commands, and running them unassisted is a daunting task. Some time ago, we introduced a set of scripts (the Tungsten Cookbook) that allow you to install multi-master topologies with a …

Summer is flying by and it's almost time to get back to school! We will be continuing our Tungsten University series on August 22nd, with a live webcast "MySQL Multi-Master Operations Made Simple With Tungsten Replicator 2.1". 

Deployment of MySQL multi-master topologies with Tungsten Replicator has been constantly improving. Yet, earlier there were some heavy operations to sustain, and

Some time ago, MySQL Forge went offline.

As part of the Forge dismissal operations, I got a backup of my snippets from the MySQL community team, and I have been lazily looking around for an alternative place where to put them.

I found such a place: Github GIST
Gist is a simple way to share snippets and pastes with others. All gists are git repositories, so they are automatically versioned, forkable and usable as a git repository.

Out of my 25 snippets, these are the ones that still look useful (at least, people have been asking me about those).

• Measuring replication speed
• Poor man's replicator monitor
• …

Overview

First off, the important news. Tungsten Replicator 2.1.0 was released today.
You can download it and give it a try right now.

Second, I would say that I am quite surprised at how much we have done in this release. The previous release (2.0.7) was in February, which is just a few months ago, and yet it looks like ages when I see the list of improvements, new features and bug fixes in the Release Notes. I did not realized it until I ran my last batch of checks to test the upgrade from the previous release, which I hadn’t run for quite a long time. It’s …

Schema definitions on replication slaves sometimes differ. Ability to rename schemas, tables and columns and still setup replication with comfort is useful for MySQL to MySQL replication, while for heterogeneous topologies like these, it's a must. In this article I'll present a component which I recently developed to enable an easy way of renaming database objects during both (a) initial slave load (provisioning) and (b) real-time replication.

It is called RenameFilter and is part of the latest Tungsten Replicator build. RenameFilter works with all DBMS types that Replicator supports.

Specifying What to Rename
First, let's look at how rename definitions file looks like. It is a CSV file which first three columns specify what to rename, while …

Use tungsten replicator to replicate between mysql and mongodb.

Mysql tables are equivalent to collections in mongodb. The replication works by replicating inserts and updates. But all DDL statements on mysql are ignored...

Replication in detail

In the replication topology I manage there are many layers of replication filters that prune data at the database and in a few places table level. The way MySQL replicates Data Definition Language (create, alter, drop) statements differs from how Data Manipulation Language (insert, update, delete) statements are handled with row-based replication. I often need to fix broken replication due to a lack of understanding of these subtle differences.

With row-based replication DML statements focus directly on the table being modified. DDL on the other hand always uses statement-based replication and is tied to what is known in MySQL as the "default database". The default database is the schema/database currently in use when a DDL …