Unobvious “Unknown column in ‘field list'” error

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...]

WebScaleSQL builds available for Debian 8 and Ubuntu 15.04

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...]

WebScaleSQL 5.6.24 is built and ready to test

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...]

Handling hierarchy and travesing Social networks in MySQL with OQGraph

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...]

MySQL Character encoding – part 2

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...]

MySQL Character encoding – part 1

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...]

WebScaleSQL RPMs available at PSCE repository

Driven by popularity of previous post about Debian/Ubuntu builds of WebScaleSQL and long discussions during FOSDEM conference this weekend, PSCE engineering team decided to put even more effort into. … [Read more...]