I’ve been designing an algorithm to resolve data differences between MySQL tables, specifically so I can ‘patch’ a replication replica that has gotten slightly out of sync without completely re-initializing it. I intend to create a tool that can identify which rows are different and bring them into sync. I would like your thoughts on this. Background and requirements I see this as the next step in my recent series of posts on MySQL tools and techniques to keep replication running reliably and smoothly.

Matt Asay proposes the following definition to the answer what consititudes an "open source company" that I blogged about yesterday: "An open source company is one that, as its core revenue-generating business, actively produces, distributes, and sells (or sells services around) software under an OSI-approved license."

I see a lot of merit in this definition. However it does shut out companies like EnterpriseDB that do proprietary extensions while feeding a lot of code back to the open source parent. Of course you can point to the fact that the product they sell is not open source.

This however is the only code based business model around BSD projects. Without picking favorites, I personally do appreciate the fact that BSD style projects produce an ecosystem that …

I have never been that interested in strict definitions of concepts and this never-ending discussion of what is and isn't open source is an interesting philosophical argument but not an entirely practical one.

There is no question that the GPL offers many benefits to companies/people who create products and release them under that license. But it's not for everyone, and there is often a necessary evolution (as Matt and SOG note) where the benefit of adoption under MPL or Apache or whatever are potentially more important than what the GPL affords.

Matt is excited about going to GPL and I back Alfresco's choice 100%. I think it makes sense for the business and where their product lives in the enterprise stack. But GPL doesn't make sense for everything (not that I think Matt believes it does, but I have had a number of people …

Right now I run into a quite common problem (see this thread on Devshed forums), people trying to load date and time related values from a flat file into MySQL and all they are getting is mangled data.
The reasons are two, first of all they are not running in a "strict" server SQL mode, which should spit errors instead of insering meaningless values (this poll shows some interest in it), the second one is related to the server datetime settings ...
As a workaround people are often tempted to mess with the input file, which is impractical when reloading large dump files, here is a quick glance at my solution, hope this helps but the usual caveats are …

SHOW PROFILES is finally available! It has been a long struggle, but finally this important community patch by Jeremy Cole has been integrated into a publicly distributed MySQL source tree (thanks to Chad Miller excellent integration work).
What's SHOW PROFILES? Is a feature to let you peek inside MySQL internals, which tell you what your queries were doing during their execution.
This feature is also remarkable because it makes a significant difference between Community and Enterprise releases.
The binaries will be available soon, but in the meantime, you can build the source code and give it a try.
BuildingTo build from source, follow the instructions at Installing from the Development Source Tree using the …

I wrote previously about looking for a more powerful search solution, and I mentioned that Xapian wasn’t quite so convenient in indexing my data. I then chose to experiment with sphinx a little more, and proceeded to create a number of search engines and indexed a number of data sources in order to decide which direction to go. Unfortunately, while sphinx was convenient and still provides an excellent backend for basic search indexes, I’m revisiting Xapian once again based on it’s more-than-anticipated flexibility. I was brief in my explanation of Xapian however, and didn’t mention some of the more important and powerful aspects of it.

Xapian provides an API

Xapian is primarily an API for search indexing/data retrieval. They do provide a handy utility called Omega (available here) for indexing static pages and a plethora of other mime-types. However, I’m in …

Doing some book packing in my office this morning (moving house soon). I didn't keep that many books when I moved from The Netherlands to Australia, so at the time I did a very tough selection. Naturally, I wouldn't toss my copy of "The C Programming Language" ;-)

One book that was given to me by my good friend Jaap van Till a long time ago is "The Networking Book - people connecting with people" by Jessica Lipnack and Jeffrey Stamps (ISBN 0-14-019116-X). It'll be out of print but I believe Amazon lists some 2nd hand sources. So why is it out of print? Because it was first published in 1986.

In 1986, what did we have... 300/1200 bps modems, FidoNet email, and that's actually what I was also involved with at the time - designing and coding datacom protocols to help people connect (some of it is actually still in use today).

Some books (and people!) are just way ahead of their time. Certainly the …

It's finally ready -- the new stable version of the innotop MySQL and InnoDB monitor. Version 1.4.0 brings you new features and enhancements I think you'll really enjoy.

I just built mysql-5.0-community, on my T7200 with 2GB of RAM (on Fedora Core 6), and it only took a mere:

real    7m51.127s

user    3m13.836s

sys     2m19.803s

The obligatory make test was run, and that was also pretty quick:

All 455 tests were successful.

The servers were restarted 109 times

Spent 1134.052 seconds actually executing testcases

Maybe we could have a competition to see how fast MySQL builds (under 8 minutes) and tests (under 19 minutes), something similar to the 7-second Linux kernel compile. With that it looks like 5.0.37 might make its way to the surface really soon now, since 5.0.35 was pending a release, before we canned that.

Why is MySQL Community Server 5.0.37 significant? Because it contains Jeremy Cole’s SHOW PROFILE feature. Notice how thats not just a patch …

Today I saw an interesting opinion posted on a mailing list. I’ll quote from the fedora-list post:

What folks say here cant be taken as Fedora toting anything. It is just some user opinions.

Some of those “user opinions” came from @redhat.com addresses, I actually don’t take any notice of @anydomain.blah posters, as they are just like I, posting a personal opinion, but when you post with @redhat.com, it is next best thing to an official comment.

And I’m wondering, is this true with all users? Does it matter if the post comes from @projectname.com or not? Are your opinions more valued if you’re employed by an open source company or the project in question?

I personally think its silly. If I make a post to mysql-list, with my @mysql.com address, I don’t expect that to be an official comment or a …