Many of you have probably already heard about the new vulnerability affecting most existing MySQL forks and versions. The bug has been patched in some of the most recent MySQL and Percona Server releases and so, at least in theory, all it takes to apply a fix is to update the MySQL or Percona Server packages to their latest versions. However, it would likely require a database restart and restarts are never particularly convenient, especially when done in a rush. But this time it is actually possible to fix the vulnerability without having to upgrade and restart your MySQL instances immediately. … [Read more...] about How to quickly patch a MySQL server against CVE-2016-6662?
Recently we got request from our customer that something is going wrong with their database and they're are getting strange errors after each insert or update to specific table. The strangeness caused by "Unknown column 'column-name' in 'field list'" message while this column was existing in this table. Our investigation shown that this was caused by trigger on the table they were trying to do the insert/update. This trigger did the insert to another table where the mentioned column didn't exist.
Let me show you example: … [Read more...] about Unobvious “Unknown column
After many months of heavy development and testing, Debian 8 (Jesse) and Ubuntu 15.04 (Vivid Vervet) were released recently. For those who already upgraded their systems and/or plan do do it in close future, we prepared builds of WebScaleSQL :-) http://repo.psce.com/download/webscalesql/deb/x86_64/vivid/ http://repo.psce.com/download/webscalesql/deb/x86_64/jessie/ You can also install it using PSCE repository. … [Read more...] about WebScaleSQL builds available for Debian 8 and Ubuntu 15.04
On Tuesday Steaphan Greene announced that all currently-pushed changes have now been rebased onto the newly-released upstream MySQL-5.6.24. … [Read more...] about WebScaleSQL 5.6.24 is built and ready to test
From time to time we detect query patterns that are not well fitted to the BTree+ structures provided by InnoDB. One such situation is when you need to traverse a hierarchy (tree) or graph structure with many nodes. Specialist databases exist for this such as Neo4J. However there exists a simple solution in the form of OQGraph which is distributed with MariaDB and is documented here. … [Read more...] about Handling hierarchy and travesing Social networks in MySQL with OQGraph
In MySQL Character encoding - part 1 we stated that the myriad of ways in which character encoding can be controlled can lead to many situations where your data may not be available as expected. … [Read more...] about MySQL Character encoding – part 2
Breaking and unbreaking your data Recently at FOSDEM, Maciej presented "Breaking and unbreaking your data", a presentation about the potential problems you can incur regarding character encoding whilst working with MySQL. In short, there are a myriad of places where character encoding can be controlled, which gives ample opportunity for the system to break and for text to become unrecoverable. … [Read more...] about MySQL Character encoding – part 1