The latest from the MySQL community

Whilst working with a client recently I noticed a large number of temporary tables being created on disk.

show global status like 'Created_tmp%'

| Created_tmp_disk_tables | 91970 |
| Created_tmp_files | 19624 |
| Created_tmp_tables | 1617031 |

Looking at a 60 second sample showed there was a steady flow of queries creating disk based tables.

mysqladmin ext -ri60

| Created_tmp_disk_tables | 74 |
| Created_tmp_files | 3 |
| Created_tmp_tables | 357 |

Luckily this client was running the Percona patched version of MySQL.

The microslow patch adds a very useful feature, the ability to log queries by execution plan.

log_slow_filter=name


Log only the queries that followed …

This is a controversial angle, and when put it like this I know many people vehemently disagree with it. Late last week, a "very high end dual site / fully redundant SAN system" at Internode failed, causing serious disruption in this ISPs various services. Internode are one of Australia's big "good guys" in ISP land and, apart from being managed by an insightful individual (Simon Hackett), they really do know their stuff technically.

I've called SANs "very expensive single points of failure". Sure, they have lots of redundancy built in, and in the case of Internode it was even physically distributed across multiple data centres. Still, something went wrong. This is because there's just an abundance of "interesting" ways to fail that are just about impossible to deal with automatically. So, SANs do have a very high uptime rating, but since big chunks of a business depend on it, any failures are quite spectacular.

Is there …

In reply to Arjen's post about Single points of failure:

Arjen, you are absolutely right.  It doesn't matter how over-engineered a storage solution is (I'm thinking of a giant dual-headed Netapp with redundant everything).  After you've paid a few hundred K for that, you still have a single point of failure.  Is it a highly-unlikely point of failure?  Sure, but it's still a point of failure. 
Let's take it a step further, at Yahoo we're beyond thinking about how to make a single node redundant (be it for storage, networking, or even a simple webserver), we consider entire datacenters to be single points of failure.  What does that mean?  

read more

A compilation of today's news of interest:

I'll be speaking at HighLoad++ conference in Moscow,Russia taking place 6,7 Oct 2008. This conference was quite success with very interesting presentation last year and I'm hoping it would be even better this year.

I also will have a full dayMaster Class focused on Scaling MySQL w Sharding and Replication based on material in our book

Interesting enough this year the conference became two another one being about same topic and very similar name taking place 22-23 September. It also sounds great and it would be hard for me to pick one or another one if not my 10 year wedding anniversary this week which made it impossible for travel.

Entry …

Today at the Riga Sun Database Group Developer Meeting, I'm giving a MySQL University session about using Launchpad.net and Bazaar for Contributors. Below, I've posted links to the slides.

A Contributor's Guide to Launchpad and Bazaar   Open Office Impress slides
  PDF slides

Topics included in the slides:

• Getting started on Launchpad
• Various features of Launchpad
• Setting up a Bazaar repository
• Bazaar Commands
• Working in a decentralized gatekeeper model
• Linking to tasks through Launchpad
• Resolving merge conflicts using Meld

Oracle's Larry Ellison has some major announcements to make during Oracle's OpenWorld conference this coming week in San Francisco. A few months ago he was promising to announce a "major database innovation", but declined to give further details, so the Oracle community has been speculating furiously.

With a keynote entitled "Extreme Performance," and product announcements coming in areas of grid computing and database acceleration, all the indications are that Oracle is getting serious about problems that require massive scalability, massive …

So, you want to compile Workbench for Linux, on Fedora 9. You need to install the following packages:

autoconf automake libtool libzip-devel libxml2-devel libsigc++20-devel libglade2-devel gtkmm24-devel mesa-libGLU-devel mysql-libs mysql mysql-devel uuid-devel lua-devel glitz-devel glitz-glx-devel pixman-devel pcre-devel libgnome-devel gtk+-devel pango-devel cairo

I feel I’m being too liberal with dependencies, but I’m not about to strip it, I just want to get it working first :)

You need to have ctemplate and ctemplate-devel installed from updates-testing-newkey (relevant koji build log).

By default, configure.in in Workbench looks for “google-ctemplate”, as opposed to just “ctemplate” as Fedora calls it. You can fix this (easy), or “cheat” - in /usr/local/include you can do sudo ln -s …

My last post Using Partitioning in MySQL™ 5.1 would be the last post of the Series “Using Feature XXX in MySQL™ 5.1″.

I started write this series of articles on August 2008 when I heard about the MySQL™ 5.1 Use Case Competition and decided to let the Community Team of MySQL™ know about what I’ve developed and included in HoneyMonitor, the HoneySoftware’s GUI for MySQL™.

I’ll comment about the 5.1 UCC later on a new post.

Here’s the links of the articles included in the series:

1. Using Partitioning in MySQL™ 5.1
2. …

This is a short tutorial on the features implemented in HoneyMonitor for the use and administration of Partitioning in MySQL™ 5.1. It could be useful for Users who are new to the product and want to get start with it or to whom want to learn the basis of Table Partitioning in MySQL™ 5.1.

Contents

1. Introduction
2. Partitioning a Table
2.1 Creating a Partitioned Table using the Create Table Wizard and the Partition Editor - A Range Partitioning Example
2.2 Partitioning a Table that already exits - An Hash Partitioning Example
3. Creating and Dropping Partitions
3.1 Adding Partitions
3.2 Dropping Range (or List) Partitions
3.2.1 Multi-Dropping of Partitions
3.3 Aggregating Hash (or Key) Partitions
4. Reorganizing Partitions
5. Repartitioning a Table
6. Removing Partitioning
7. Retrieving Information about Partitions
7.1 Partitions’ …