Hi – I’m Walt Weeks, Engineering Manager at Calpont. We are pleased to announce the availability of the 0.9.5.0-0 release of InfiniDB Community Edition. This is our latest alpha release and is not recommended for production work.
New functionality we’ve added with 0.9.5.0 includes:
The ability to add new columns to existing tables in an online
fashion – something we know Read More...
Hi – I’m Walt Weeks, Engineering Manager at Calpont. We are pleased to announce the availability of the 0.9.5.0-0 release of InfiniDB Community Edition. This is our latest alpha release and is not recommended for production work.
New functionality we’ve added with 0.9.5.0 includes:
The ability to add new columns to existing tables in an online
fashion – something we know Read More...
There will be a series of posts to help describe InfiniDB join
behavior to help understand what is possible as join conditions
change.
Join Profiling Topics:
1) Profiling Overview (this post) - Profile a 5 table join
as cardinality changes. Show scalability.
2) Profiling Multi-Join - Explain and measure InfiniDB
Multi-Join (join n tables in 1 scalable operation). Profile
scalability.
3) Profile In vs. Hash Join - Compare In (list)
performanceRead More...
Image by Nathan Lanier via Flickr
<< Back from Blogging Hiatus - Update 2
IngresNo specific announcements from Ingres other than I
think the VectorWise stuff is progressing well.
To me Ingres is a bit of a dark horse. They are open source
and doing reasonable revenues. And they are active in the
enterprise market (something MySQL hasn’t really achieved).
But they remain largely off the radar in commentary surrounding
the DBMS industry.
My personal pick is this will start to change …
As eWeek reports, the EC handed down a formal objection to the Oracle-Sun deal. To quote the article:
The regulators see a major conflict of interest in the world's largest commercial database company owning its largest open source competitor.
Oracle responded with a statement yesterday. To quote from it:
It is well understood by those knowledgeable about open source software that because MySQL is open source, it cannot be controlled by anyone.
Yes, thank God that true Open Source (as we knew it 10 years ago) can't be controlled by anyone and everybody has the right to fork the software (as has already been done by forking into Drizzle or …
[Read more]Sun Virtual Desktop Infrastructure (VDI3) is a desktop virtualization technology that provides virtual desktop access, brokering, and hosting, enabling Windows, OpenSolaris, or Linux virtual desktops. These desktops can be accessed by using existing PCs, Macs or thin clients such as Sun Ray.
In a procedural language without the use of threads (or Inter
Process Communication via forks), to execute I/O requests they
are done one after another. Synchronous Queries produce at best a
Big-O of N such that N is an element of I/O communication
(queries) and N equals the number of queries needed to achieve
the requested dataset.
With IPC or threads we can speed up common O(N) problems to
reduce the N with parallelism, its still functionally a O(N) yet
from a single instance point of view N is much less because
threads (IPC) takes that Serial computing component and executes
the code in parallel. To better explain what I am talking about
lets look at some PHP code:
foreach($friends as $friend){
$data[] = getMySQLData(“SELECT * FROM AccountData WHERE userid = $friend);
}
The Primary key for the AccountData table is userid. Assuming
that you have 5000 friends, the …
A very interesting problem came up a while back when testing a
rebuild and failover procedure. I had just run a rebuild of a
slave server with InnoDB Hot Backup from the master. After the
failover, one query on three tables in three different databases
was not performing as it should. This was very odd to me given
that the same table in all three databases was acting up. Below
is the table structure and example query:
mysql> show create table plx_async_job\\\\G
*************************** 1. row
***************************
Table: plx_async_job
Create Table: CREATE TABLE `plx_async_job` (
`async_job_id` int(11) NOT NULL AUTO_INCREMENT,
`db_id` tinyint(3) unsigned NOT NULL DEFAULT '0',
`user_id` int(11) NOT NULL DEFAULT '0',
`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
`modified` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
`job_status` tinyint(4) NOT …
I've recently been accumulating some MySQL configuration variables that have defaults which have proven to be problematic in a high-volume production environment. The thing they all have in common is a network blip or two can trigger some very undesirable behavior.
max_connect_errors
If a client is having trouble connecting to MySQL, the server
will give up waiting after connect_timeout seconds and
increment the counter which tracks the number of connect errors
it has seen for the host. Then, when that value reaches
max_connect_errors, the client will be
locked out until you issue a FLUSH HOSTS command.
Worse yet, if you have occasionally network blips and never need
to restart your MySQL boxes, these errors can accumulate over
time and eventually cause you middle of the night …
During this autumn I've had the pleasure of working closely with Georg Greve, Founder and former President of the Free Software Foundation Europe. Seeing that he had just left his previous post, we realized that his experience would be invaluable to do some of the heavy lifting involved in setting up processes for this fresh association. And so it has been!
As a result, we now have mundane things like a post box and accountant in Zurich where the non-profit association has its legal home. We are finally able to accept membership applications through the new website.