The latest from the MySQL community

In one of the last commits I added a SQL Tokenizer which understands the basic tokens of (My)SQL:

• Strings
• Literals
• Numbers
• Comments
• Operators

With this basic understanding we can normalize Queries and build statistics over similar queries.

The idea is simple and already implemented in mysqldumpslow:

/* login.php:37 */SELECT * FROM tbl WHERE id = 1243 AND name = "jan"

is turned into

  SELECT * FROM `tbl` WHERE `id` = ? AND `name` = ?

The queries look like prepared statements now and can be used the characterize queries of the same kind.

• comments are removed
• whitespaces are stripped
• literals are quoted
• constants are replaced with ?

Taking the famous world-db and executing some simple queries like:

root@127.0.0.1:4040 …

I came across this issue sometime last year, got the solution from the resident Emacs wizard and forgot about it. Last week, it happened again. I'm recording it now so I don't forget about it.

Emacs lets you search and replace in a buffer with regular expressions. So far so cool. I needed to replace a part of a lot of HTML links in a file.

<a href="/path/to/file" title="some title">Go!</a>

was to become

<a href="/path/to/file" title="other title">Go!</a>

with varying values for the title attribute obviously. So I searched for

    <a href="/path/to/file" title="([^\"]*)">Go!</a>

and Emacs complained about some invalid regex. Darn. I double and triple checked all necessary escape sequences (which I omitted here for clarity) and finally asked the wizard.

Easy, Emacs doesn't konw the * quantifier. Do …

InnoDB: Number of pending reads 128, pending pread calls 0
InnoDB: Error: InnoDB has waited for 50 seconds for pending
InnoDB: reads to the buffer pool to be finished.

What does this mean? Well searching yahoo search I couldn't find anything other then pointers to source code where this message generated. I assumed it was a disk problem because performance was super crappy.

My disk monitoring software which probes MegaRaidCli didn't report a failed disk. Linux didn't report a failed disk or any errors. So, what is happening? Was I wrong?

Well, in fact it was a failed disk, but not in a state that could be classified as failed by the controller or any other component including the OS. With the help of my bud we found that a disk in the array was in a critical state-the disk itself just had a bunch of sector errors, yet the controller, os, everything would not mark it as dead - so the end result …

We have started MySQL Camp II. The first session is Introductions.

I didn’t catch all the employers, but here is part of the list of attendees at the Introduction section. Great to see multiple people from many places including ESPN, priceline.com, Proven Scaling, Solid Tech - sponsors of Dorsal Source, ForSaleByOwner. fontshop.com, 9Mmedia, CafeMom, JP Morgan, …

We have started MySQL Camp II . The first session is Introductions. I didn’t catch all the employers, but here is part of the list of attendees at the Introduction section.

We have started MySQL Camp II . The first session is Introductions. I didn’t catch all the employers, but here is part of the list of attendees at the Introduction section.

I mentioned this event a few weeks ago, but it's worth a reminder.

The Free and Open Source Software Conference is held in Sankt Augustin, a cheerful place near Bonn.


Some reasons to attend:

• the organizers are friendly and efficient
• the program is exciting
• the food is good,
• it's full of open source enthusiasts
• I am meeting with a bunch of friends and colleagues

Do you need more? Ah, yes, my session :)
I will present a topic for database administrators, Monitoring and logging a database server.
But there is also Lenz …

Well readers, your either here or your not. MySQL Camp II starts today in Brooklyn, New York, at Polytechnic University. Last night’s pre drinks meetup in NYC went well, but today it’s brass tacks time. View Larger Map

For those of you not able to make it, IRC@Freenode #mysql-camp will be the place to hang out to hear what’s happening. If your not at the camp, please identify yourself. Be sure to also check out the Camp Web Site MySQL Camp II for the plans for today and tomorrow.

For those of you not here, MySQL Camp III is already in planning.

Well readers, your either here or your not. MySQL Camp II starts today in Brooklyn, New York, at Polytechnic University. Last night’s pre drinks meetup in NYC went well, but today it’s brass tacks time.

Well readers, your either here or your not. MySQL Camp II starts today in Brooklyn, New York, at Polytechnic University. Last night’s pre drinks meetup in NYC went well, but today it’s brass tacks time.