Hooray for Data Structures… Where Are They?

The Key-Value Pair is my favorite programming tool. Most SQL type databases lack this feature in it simplest form. Some would argue, “Well that’s because databases don’t need dah-blah-dee-blah-blah…” Well, if they don’t need it I don’t need to write this post. :p

How many times have you found yourself asking “Why isn’t there at least simple array support!?” When you don’t want the overhead of creating a table, or a temporary table, simple data structures really do come in handy (hint, hint, nudge, nudge to all the companies producing database software with stored routine support).

I’m not one to let an apparent lack of functionality ruin my day. Instead, I add it. I had a great computer science professor who said “You don’t need pointers to create a linked list.” Then he proved it. You can create, pretty much, any abstract data structure with …

you can try to run mysql_upgrade to repair and update database medadata information. Not sure if mysql_upgrade available in mysql server 4.x or not. give it a try !!!

In the past I have written about MySQL's limitations that prevent you from creating an index over a certain length, or with more than a certain number of columns. I've offered some solutions for those problems, but many of my solutions hit another limit further down the line. For example innodb_large_prefix allows you to create an index on larger columns, but only up to 3072 bytes, and my workarounds for the 16 column limit per index will also hit that 3072 byte limit once you add lots of columns or add some very long columns.

Today I'm going to suggest a …

Greetings everyone! Let’s discuss a 3rd Party auditing solution to MySQL and how we can leverage MongoDB® to make sense out of all of that data.

The McAfee MySQL Audit plugin does a great job of capturing, at low level, activities within a MySQL server. It does this through some non-standard APIs which is why installing and configuring the plugin can be a bit difficult. The audit information is stored in JSON format, in a text file, by default.

There is 1 JSON object for each action that takes place within MySQL. If a user logs in, there’s an object. If that user queries a table, there’s an object. Imagine 1000 active connections from an application, each doing 2 queries per second. That’s 2000 JSON objects per second being written to the audit log. After 24 hours, that would be almost 173,000,000 audit entries!

How does one make sense of that many JSON objects? One option would be to write your own parser in …

The MySQL 5.7.7 JSON lab release has been getting a lot of attention. At a recent conference, I was cornered by a developer who wanted to jump in with both feet by running this release on his laptop on the flight home. However the developer was not sure how to begin.

1. Down load the MySQL JSON release from http://labs.mysql.com/. You will get the choice of a Linux binary or source code. Please grab the binary if you are using Linux and un-gzip/tar the download.

2. Shut down the current running version of MySQL. I was lucky in this case that the developer was using a recent copy of Ubuntu.

3. Change directory to the ~/Downloads/mysql-5.7.7-labs-json-linux-el6-x86_64 directory.

4. sudo ./bin/mysqld_safe –user=mysql&

5. ./bin/mysql -u root -p, then provde the …

This Log Buffer edition transcends beyond ordinary and loop in few of the very good blog posts from Oracle, SQL Server and MySQL.

Oracle:

• Variable selection also known as feature or attribute selection is an important technique for data mining and predictive analytics.
• The Oracle Utilities SDK V4.3.0.0.2 has been released and is available from My Oracle Support for download.
• This article provides a high level list of the new features that exist in HFM 11.1.2.4 and details the changes/differences between HFM 11.1.2.4 and previous releases.
• In recent …

One of the challenges in storage engine design is random I/O during a write operation. In InnoDB, a table will have one clustered index and zero or more secondary indexes.  Each of these indexes is a B-tree.  When a record is inserted into a table, the record is first inserted into clustered index and then into each of the secondary indexes.  So, the resulting I/O operation will be randomly distributed across the disk.  The I/O pattern is similarly random for update and delete operations. To mitigate this problem, the InnoDB storage engine uses a special data structure called the change buffer (previously known as the insert buffer, which is while you will see ibuf and IBUF used in various internal names).

The change buffer is another B-tree, with the ability to hold the record of any secondary index.  It is also …

Introduction

The Galera Cluster Juju Charm was recently released, and it is now possible to start scalable Galera Clusters using the Juju deployment framework on the public or private cloud (OpenStack, Amazon, Azure and bare metal are all supported). All the logic required to fire up Galera is encapsulated in the Charm, which is a small package of scripts and configuration files that is automatically downloaded and added to your environment.

Installing and Configuring Juju

The Juju client is available for Ubuntu, OSX and Windows. Installing it is a matter of adding its dedicated package repository:

$ sudo add-apt-repository ppa:juju/stable
$ sudo apt-get update && sudo apt-get install juju-core

Then run

$ juju generate-config

in order to create the Juju configuration file, ~/.juju/environments.yaml, which you can then edit for your particular cloud …

Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on June 3rd 2015. Binaries are available from downloads area or from our software repositories.

Based on Percona Server 5.6.24-72.2 including all the bug fixes in it, Galera Replicator 3.11, and on …

In the MySQL ecosystem there are few load balancers there are also open-source, and ProxySQL is one of the few proxies that works at the application layer and therefore is SQL aware.
In this blog post we will benchmark ProxySQL against MaxScale, another popular proxy for MySQL.
The idea to compare ProxySQL vs MaxScale came after reading an interesting blog post of Krzysztof Książek on SQL Load Balancing Benchmark, comparing performance of MaxScale vs HAProxy.

Disclaimer: ProxySQL is not GA yet, therefore please do not use it in production.



Sysbench setupI wanted to setup a similar sysbench setup to what Krzysztof used in his benchmark, but it is slightly different:
a) instead of using a MySQL cluster with Galera, I setup a cluster with 1 master …