Have you ever wondered exactly does log_warnings=2 log? Well, I have, and finally decided to check the code. (The manual used to mention setting this to 2 for diagnosing some connection-related problems, but I didn’t run into that comment in my most recent search.)

Basically, in recent 5.6 source code, we find “log_warnings > 1″ in 7 files. In 5.5 source, it is only in 5 files. Here are the 7 files in 5.6:

filesort.cc (line 460)
log_event.cc (lines 4873, 10020, 11209)
rpl_master.cc (line 912)
rpl_rli_pdb.cc (lines 1538, 1596, 1735, 2066)
rpl_slave.cc (lines 3585, 4684, 5405, 5436)
sql_acl.cc (lines 9591, 9613, 11351)
sql_connect.cc (line 791)

Long story short, the main (most common) ones are when a filesort fails (filesort.cc) or a failed login occurs (sql_acl.cc). Then there are some replication-specific instances where it logs extra info, such as master/slave/binlog info, “ignored” errors, and some summary stats …

The latest set of updates for MaxScale has just been released, among the highlights of this alpha release are improved Galera support, the introduction of the first phase of the filter API and server maintenance mode.

Galera SupportMaxScale has always supported Galera, at least since the earliest downloadable release, now it has the ability to use Galera in a different way.
The initial Galera support simply involved using the Galera Monitor plugin to provide the routers with information as the the state of each of the nodes in the Galera Cluster. This meant that routing of queries could be controlled such that queries would only be sent to nodes that were fully fledged members of the cluster. No statements would get sent to a node whilst it was still joining a cluster or during state transfers.
The latest release provides a new monitor mechanism that as well as being able to report the state of the nodes …

MaxScale 0.7.0 was recently released (it is the 4th alpha, with the beta on the near horizon), and is available for download here.

The release contains a number of new enhancements as well as 8 bugs fixes.

Enhancements:

1. Galera Support: Enhanced support for Galera cluster to allow Galera to be used as a High Available Cluster with no write contention between the nodes. MaxScale will control access to a Galera Cluster such that one node is designated as the master node to which all write operations will be sent. Read operations will be sent to any of the remaining nodes that are part of the cluster. Should the currently elected master node fail MaxScale will automatically promote one of the remaining nodes to become the new master node.
2. Multiple Slave Connections: The Read/Write …

MySQL has an extensive range of high-availability solutions to suit many different use cases and deployment needs.  This list spans from the time-tested – yet continuously-improved – MySQL replication to the just-released MySQL Fabric, giving users many certified solutions for highly available MySQL deployments.  The list is growing yet again, with Oracle Clusterware adding support for MySQL.

Oracle’s Clusterware product is the foundation for the Oracle RAC, and has been battle-tested for high availability support for Oracle database, as well as other Oracle applications.  This technology is now available as part of the MySQL Enterprise subscription, and – like all Oracle commercial products – is …

The Hadoop Summit, a leading Apache Hadoop industry conference, has grown significantly over the years, and throughout the day, theCUBE, led by hosts John Furrier and Jeff Kelly, featured the best of thought leaders, use cases, data scientists, data analysts, and developers at the event. Watch yesterday's interview with Robert Hodges (CEO, Continuent) on real-time data loading from Oracle and

A small team from MariaDB and SkySQL joined up in the Lone Star State for the 2014 Durpal Con in Austin this week. Why MariaDB and MySQL at Drupal Con? Because almost every person that we met was using MySQL as their back-end, and each of them can benefit from a potential performance increase simply by moving to MariaDB - more on that to follow

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In this blog post we are going to talk about one of the features included since MySQL for Excel 1.2.0, we introduced some advanced options for the Import MySQL Data operation regarding Excel tables. You can install the latest GA or maintenance version using the MySQL Installer or optionally you can download directly any GA or non-GA version from the MySQL Developer Zone.

Cloud computing makes it very affordable to get your own private virtual server on the Internet. Digital Ocean offers an entry level droplet for USD$5 per month, and Amazon.com has a micro instance tier on the EC2 platform that is free for the first year. These instances are rather useful if you want to test out some new technologies (multi source replication?) or put together a proof of concept.

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Due to all of the positive feedback that I received on the MySQL 5.7.3 & 5.7.4 blog posts, I have decided to complete the picture by doing the same for 5.7.1 & 5.7.2. Note that you will find historical releases — including milestone releases — at downloads.mysql.com.

So here is the belated post for the MySQL 5.7.1 Milestone Release, released on April 22, 2013. You can find the full list of changes and bug fixes in the 5.7.1 Release Notes. Enjoy!

InnoDB Online Alter Table

Online Rename Index This work by Marko …

If you read Yoshinori's post about Semi-sync at Facebook, he lists the objective of using semi-sync as an alternative to running full durability on a master. That is to say that once you can guarantee writes have safely been shipped across the network, you may not strictly need to guarantee that they are safe locally.

This is something that I have been wanting to benchmark for a long time, and reading Jay's post about Semi-sync replication performance in MySQL 5.7 DMR4 and a conversation in last week's #dbhangops inspired me to explore this in more detail. For my tests, I will be using Master-Slave replication and three alternative definitions of durability:

• Local …