MySQL replication isn’t perfect and sometimes our data gets out of sync, either by a failure in replication or human intervention. We are all familiar with Percona Toolkit’s pt-table-checksum and pt-table-sync to help us check and fix data inconsistencies – but imagine the following scenario where we mix regular replication with the Tungsten Replicator:

We have regular replication going from master (db1) to 4 slaves (db2, db3, db4 and db5), but also we find that db3 is also master of db4 and db5 using Tungsten replication for 1 database called test. This setup is currently working this way because it was deployed some time ago when multi-source replication was not possible using regular MySQL replication. This is now a working feature in …

A much awaited release from the MariaDB project is now stable (GA) – MariaDB Galera Cluster 10.0.12. This is a complete merge of MariaDB 10.0.12 and Galera Cluster, with additional features and bug fixes. This gives you the entire power of Galera Cluster as well as the benefits of all the MariaDB 10 features. 

This is the fourth release in the 10.0 Galera Cluster series, and for more changes, please review the …

What’s the connection between databases and fruit flies?
Some of you may be familiar with the bestseller in business literature The Innovator's Dilemma: When New Technologies Cause Great Firms to Fail, by Harvard professor Clayton Christensen. In his book, Prof. Christensen compared disk drives to fruit flies. The comparison relates to the rapid changes that disrupted the disk drive industry for decades. That disruption is compared to the rapid changes that take place to fruit flies that live only for few hours, and for this reason researchers can study and analyse their behaviour.

In the software business, you can replace disk drives with databases. Obviously, databases live longer than fruit flies, but it is an industry that sometimes shows schizophrenic changes. Whilst it is true that relational databases have being dominated the scene for decades, readers with grey hair and reading glasses have …

MariaDB 10 is nearing GA, and it makes sense to make sure that the test suite from MySQL 5.6 is merged into MariaDB 10. Svoj is doing a lot of this work, and then we like to look at features, especially ones that are deprecated upstream. We don’t do that on blogs, but on the maria-developers mailing list.

I bring to your attention: Intermediate status for test cases merge. We see that INSERT DELAYED and SHOW PROFILE for example are deprecated in MySQL 5.6. The only way for feedback to the MySQL team seems to be comments on Morgan’s blog. However with MariaDB, especially with the feedback plugin enabled, we have an additional layer of …

MaxScale is the new proxy server from the SkySQL/MariaDB team. It provides Connection Load Balancing (CLB) and Statement Load Balancing (SLB) out of the box. This post is a [relatively] quick “how to” install, configure and test SLB with the read/write splitting module.

Step 1 - Server preparationIf you do not have many HW resources, you may run everything on a single Linux instance, but the best way to test MaxScale is to use at least 4 servers: one for MaxScale and for the client apps, one as Master and two as slaves - so, 4 in total. In this post I am going a bit further, I will use 5 servers:
Max 0 - For client apps (192.168.56.20)
Max 1 - The master server (192.168.56.21)
Max 2 - The first slave (192.168.56.22)
Max 3 - The second slave (192.168.56.23)
Max 4 - The third slave (192.168.56.24)
Max 6 - The MaxScale server (192.168.56.26)

In order to do proper tests …

In many parts of the MySQL world, whether you have users, developers or administrators of MySQL, the season holidays are for family, relax, prayers, travel, or they are simply a moment where you can enjoy what you like or care most about.

For me, this time is dedicated to my family, but also to deeper thoughts around the strategies to adopt in short and long term. My work nowadays, as the work of many others, is ruled by quick decisions, by the "time to market” - whatever “market" means in a specific context. Decisions must be made in meetings that are time-boxed in one hour or even less. In the end, you accumulate so much work and high priority tasks that you do not have enough time to prepare the topics adequately.

I thought I could summarise my thoughts for the past year and for the near future, from a technical and from a business perspective.

A transient 2013To me, 2013 was a transient …

For my 25 readers (Italians would know better, citing The Betrothed by Alessandro Manzoni): if you are a techie and you do not know me , you can stop reading. No tech tips inside, nor 5 gazillion queries per second improvement in this post, sorry!

On the other hand, if curiosity is what drives you through the posts of PlanetMySQL  you may find bits in this post of some interest, or even helpful.

Few days ago I opened my blog and found the last post, dated April 2013. It was a reminder for the readers that the OpenStack Summit …

It’s time to unveil the winners of the [Plus] readers choice awards!
Thank you again for your votes, remember that the real winner was the community, again.

I asked you to vote for what you used in 2012 and you’ve voted with your heart.
Here are the final results, congrats to the lucky guys and teams :

The most useful blogs in 2012 :

1. MySQL Performance Blog
2. The MariaDB Blog
3. SkySQL Blog

Ok, the Percona team members provides the best technical blog about MySQL (and more), this year again. Of course, this blog is very useful and interesting, I recommend to read the comments too, they are often very informative.
There is a …

First, congratulations Oracle on the GA of MySQL 5.6! Well done!

In this post I walkthrough the features of the first two alpha versions of MariaDB 10.0. The first, 10.0.0-alpha, which was made available in November, and 10.0.1-alpha that saw daylight yesterday. I will go through the features by placing them in the following categories:

• MariaDB 10.0-only Features (features that aren’t in MySQL 5.6)
• MariaDB 10.0 Merged Features (features merged from MySQL 5.6)
• MariaDB 10.0 Reimplemented Features (features reimplemented from features in MySQL 5.6)
• MariaDB 5.x Features now in MySQL 5.6 (features introduced in earlier MariaDB versions which have now been introduced in MySQL 5.6)
• MariaDB 5.x Features Backported from MySQL 5.6 (features introduced in earlier MariaDB versions which were backports of features from MySQL 5.6 development …

Oh yes, 2012 was an incredible year for the MySQL Community!
That’s why I would like to change the rules this year and I would like to offer you a new survey for this [Plus] reader’s choice 2012.

Community users, bloggers and events made the whole community last year, tell us how you used this community?
It will only take 5 minutes of your precious time, votes will be closed Jan. 31.

Vote for what you used! (with your heart, again…)

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit the site to participate in this post's poll.

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