This article shows how to find duplicated rows in a database table. This is a very common beginner question. The basic technique is straightforward. I’ll also show some variations, such as how to find “duplicates in two columns” (a recent question on the #mysql IRC channel). How to find duplicated rows The first step is to define what exactly makes a row a duplicate of another row. Most of the time this is easy: they have the same value in some column.

Yesterday I had fun time repairing 1.5Tb ext3 partition, containing many millions of files. Of course it should have never happened - this was decent PowerEdge 2850 box with RAID volume, ECC memory and reliable CentOS 4.4 distribution but still it did. We had "journal failed" message in kernel log and filesystem needed to be checked and repaired even though it is journaling file system which should not need checks in normal use, even in case of power failures. Checking and repairing took many hours especially as automatic check on boot failed and had to be manually restarted.

Same may happen with Innodb tables. They are designed to never crash, surviving power failures and even partial page writes but still they can get corrupted because of MySQL bugs, OS Bugs or hardware bugs, misconfiguration or failures.

Sometimes corruption kind be mild, so ALTER TABLE to rebuild the table fixes it. Sometimes table needs to be dropped and …

I left Brisbane about 1 month ago, not knowing exactly when I would come back. Now I think I know that answer - I don't know if I will come back in a permanent sense for quite a while (but I'll be back for Christmas, and a wedding early next year). Bangkok is not my final stop though - I'm likely going to flee this place in another month; the night-life is pretty cool, but it corrupts you. Things that you don't approve of are happening in public. You don't see them at first, but once someone points them out to you, you can't miss them.

I've met a couple of good buddies now. Which surprises me, I thought that that would be the difficult part. There seems to be a bit of comradely between the expats. I came here by choice, to experience something a little different. A lot of the guys came here to work, and their company sent them to train local Thai people. There are some cultural value differences that mean that the thai people need the …

Want to say sorry to all my Russian language readers because my Russian Feed has been broken for last week or so after hoster changes. As for now feed works fine and you can read my last post in your native language!

It will be really short post about using set of free tools to implement fully functional flash video streaming server. So, what we are going to get at the end of our setup? We are going to get some type of completely free streaming support that is available with Macromedia’s non-free Flash Communication Server (Flash Media Server) (FCS).

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I do not know enough about the subject to answer this, but I know the folks that read this do.

From: http://mysql.meetup.com/137/boards/view/viewthread?thread=2280640

Hi,

I wonder is there any way to call an application which resides on the database server computer from stored procedure or trigger? Is the language of stored procedures and triggers only restricted by SQL statements and some arithmetic operations?

It is interesting that Oracle and MS SQL Server already have this functionality. In Oracle it is Java stored procedure, in MS SQL Server it is called “extended stored procedure” where you can call C++ routine out of your stored procedure. It is difficult overestimate the convenience of being able to do some processing triggerted by the record insertion event.

In this case the database could be …

In my most recent blog entry, I reported on the pretty reasonable compromise the three largest groups in the European Parliament have reached on the upcoming resolution on future European patent policy.

Meanwhile, Dow Jones has quoted Erika Mann MEP, a German social democrat who is very much in favor of software patents, as saying that the EP has, through this compromise, effectively “postponed” a decision on the EPLA. I would not contradict that assessment. The proposed resolution neither urges the Commission to drop its EPLA-related plans nor does it support the EPLA in its present form. It ends up saying very little, if anything at all, by accepting that the Commission may have …

All German speaking folks will have a chance to get a printed German MySQL 5.1 Reference Manual which covering 1,312 pages for a price of EUR 59.95 (hey, most books with that amount of pages cost much more than that).

It is about to be released this month and can be pre-ordered at amazon.de.

I pre-ordered my copy today. Sometimes it's nice to leave the PC for a while and dig into a good book, but still use the time to improve skills. There are still some topics about MySQL that I'm not as familiar with as I wished and this will be good opportunity to remove some gaps in my knowledge.

Unlike fellow author Giuseppe of last week’s Log Buffer #12 I volunteered for the job of this week’s Log Buffer. Lots to say, so little time, so lets get started with Log Buffer #13.

Tom Kyte has been at the DBForum 2006 in Denmark. Apart from the contents of the Forum, his picture and comment “I spied some artifacts from Mogens Oracle Museum, a copy of the Version 3 and Version 4 Oracle” in Dbforum 2006, in the past… was an impressive look back in time. Manuals, what are they? So how old is this? Wikipedia …

Like fellow friends and MySQL’ers before me Morgan, Roland, Giuseppe, Markus and Sean, I’ve joined the MySQL juggernaut on the ride of my life, achieving two of my short/medium term professional goals in one step. Woot!

It says something to me about the company I’m very excited to work for when I knew of all these people before they joined MySQL this year (2006). I’ll also be joining other friends and MySQL people Arjen, Jon, …