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Showing entries 1 to 30 of 35 Next 5 Older Entries

Displaying posts with tag: Random (reset)

Create random test data using real data from your MySql database.
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Generate useful test data and random dates in MySql. All code and tables are provided.
MySql Lorum Ipsum generator
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A short MySql function to generate a Lorum Ipsum text. You can download the code in the zip file below.
Howto generate meaningful test data using a MySQL function
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You can use this MySQL function to generate names, (e-mail)addresses, phone numbers, urls, bit values, colors, IP address, etc.. As usual, the code is provided in a zip and the code is fully documented.
Taxonomy of database tools
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Taxonomy of Database Tools

In the MySQL ecosphere there is an ecosystem of tools.  Like real-world ecosystems, the “creatures” in the MySQL tools ecosystem can be classified and organized by a taxonomy.  There are already multiple taxonomies of software bugs (e.g. A Taxonomy of Bugs), but as far as I know this is the first Taxonomy of Database Tools.  A taxonomy of database tools serves useful purposes, as discussed in the previously linked page.  For me, the most useful purpose is the high-level ecosystem view which I


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PT BOF at PLMCE 2012
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PT BOF at PLMCE 2012, or: I submitted a session for Percona Toolkit Birds of a Feather at Percona Live MySQL Conference & Expo 2012. You should BoF too; hard deadline is Monday, March 12th: submit a BoF session, or submit a Lightning Talk.

Truly Random and Complex Password Generator - Part 1 of 2
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Permalink: http://bit.ly/1pJlpHz



Skip to the 2nd part for the code snippet.

Its an important matter of security to enforce complex passwords that have a sufficient length. From personal experience, if you ask a normal user to create their own passwords, their passwords will be based on a character set consisting of 36 case-insensitive alphanumeric characters: a-z, 0-9 instead of the full 94 character set typable on all keyboard layouts. Also, most normal users would use dictionary based passwords with a predictable pattern: dictionary words at the beginning and numbers at the end.

Relying solely on the client-side or front-end to enforce the







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How to select random rows in MySQL
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The easiest way to generate random rows in MySQL is to use the ORDER BY RAND() clause. SELECT col1 FROM tbl ORDER BY RAND() LIMIT 10; This can work fine for small tables. However, for big table, it will have a serious performance problem as in order to generate the list of random rows, MySQL […]
MySQL Random Data Selection
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Some days ago I was working in a vocabulary game and dictionary. The dictionary contains 1,10,000 words and meanings. I developed a vocabulary game where I had to randomly choose 10 words out of 1,10,000 dataset. Here I’m describing the possible solutions for retrieving 10 random words from 1,10,000…  Read Full Article


Setting the MySQL Sandbox prompt
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This is far from deeply technical but little things that should be simple but aren’t annoy me. I found that MySQL Sandbox --prompt_prefix and --prompt_body don’t “just work.” I wanted the prompt to be mysql \v> . So I tried:

make_sandbox_from_source /mysql/src/mysql-4.0.30 single --prompt_body=' \v> '
sh: -c: line 0: syntax error near unexpected token `newline'
sh: -c: line 0: `make_sandbox /mysql/src/mysql-4.0.30/4.0.30 --prompt_body= \v> '

Maybe my shell knowledge is more terrible than I realize so I verified that ‘ \v> ‘ does not need special escaping:

echo ' \v> '
\v>

Ok, so clearly it’s the fault of










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OpenSQL Camp 2009 in Portland, Oregon
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There’s very few spots left for attending OpenSQL Camp 2009. I’m going, along with several other Percona employees. It’s fun stuff; you should go. I’m not really the social type so I’ll probably be sitting off to the side somewhere coding.

Scalability and Stability for SysBench on Solaris
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My mind is playing "Suffering Succotash..."

I have been working on MySQL performance for a while now, and the team I am in have discovered that SysBench could do with a couple of tweaks for Solaris.

Sidebar - sysbench is a simple "OLTP" benchmark which can test multiple databases, including MySQL. Find out all about it here , but go to the download page to get the latest version.

To simulate multiple users sending requests to a database, sysbench uses multiple threads. This leads to two issues we have identified with SysBench on Solaris, namely:

  • The implementation of random() is explicitly identified as unsafe in multi-threaded applications on Solaris. My team has found

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Scalability and Stability for SysBench on Solaris
Employee +0 Vote Up -0Vote Down

My mind is playing "Suffering Succotash..."

I have been working on MySQL performance for a while now, and the team I am in have discovered that SysBench could do with a couple of tweaks for Solaris.

Sidebar - sysbench is a simple "OLTP" benchmark which can test multiple databases, including MySQL. Find out all about it here , but go to the download page to get the latest version.

To simulate multiple users sending requests to a database, sysbench uses multiple threads. This leads to two issues we have identified with SysBench on Solaris, namely:

  • The implementation of random() is explicitly identified as unsafe in multi-threaded applications on Solaris. My team has found

  [Read more...]
Scalability and Stability for SysBench on Solaris
Employee +0 Vote Up -0Vote Down

My mind is playing "Suffering Succotash..."

I have been working on MySQL performance for a while now, and the team I am in have discovered that SysBench could do with a couple of tweaks for Solaris.

Sidebar - sysbench is a simple "OLTP" benchmark which can test multiple databases, including MySQL. Find out all about it here , but go to the download page to get the latest version.

To simulate multiple users sending requests to a database, sysbench uses multiple threads. This leads to two issues we have identified with SysBench on Solaris, namely:

  • The implementation of random() is explicitly identified as unsafe in multi-threaded applications on Solaris. My team has

  [Read more...]
MySQL University: Random Query Generator
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This Thursday (December 11th), Philip Stoev will talk about the Random Query Generator, a new QA tool that generates pseudo-random queries targeted to exercise a specific part of the server being tested. It then executes those queries to check for crashes or assertions or to compare the results returned from two different servers (two versions, two different storage engines, optimizer flags, etc.). It is also able to execute queries against a replication master, constantly checking that the slave is okay and has not diverged.

Towards the end of the session, Philip will share his desktop and show some live examples. Make sure to adjust your volume in

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MySQL University for up to 100 attendees
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Yesterday (December 4th), Sergey Petrunia gave a presentation on what's new in MySQL Optimizer. Unfortunately, the slides didn't show up in the Dimdim presentation area, which also means that the recorded session only has Sergey's voice but not the slides. (I've filed a bug in Dimdim's issue tracker.) However, Sergey kept referring to slide numbers in his talk, so it should be fairly easy (just not as convenient as usual) to follow his recorded presentation.

The slides, together with links to the recording and the chat transcript, can be found

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Two Tech Jobs: Technology Evangelist and Network Operations
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I've been getting lots of inquiries from recruiters recently looking to find good people for various tech companies. Two in particular might be interesting if you're in the market or know someone who is.

Technology Evangelist at New York City Based Startup

If you saw Fred Wilson's post Are You A Connector?, you know a bit about this job already. It's a NYC based startup developing a new platform in an area that's likely to see serious growth in the next few years.

They're looking for someone with coding experience who loves showing other developers and users how stuff works: on stage, via blogs, in screencasts, and so on. It's important that this person have a technical (programming) background and also be very comfortable getting in front of people to demo and speak.

The company is New

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Random Timestamps in MySQL
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Have you ever needed a random timestamp in MySQL? For example to create demo data programmatically? Here’s my solution:

SELECT FROM_UNIXTIME(
  FLOOR(
    UNIX_TIMESTAMP('2007-01-01') +
        RAND() *
	(UNIX_TIMESTAMP('2007-01-03')-UNIX_TIMESTAMP('2007-01-01'))
    )
) as random_timestamp;

Or if you prefer a function:

CREATE FUNCTION random_timestamp (start TIMESTAMP, end TIMESTAMP)
RETURNS TIMESTAMP NOT DETERMINISTIC
RETURN FROM_UNIXTIME(
  FLOOR(
    UNIX_TIMESTAMP(start) +
    RAND() *
    (UNIX_TIMESTAMP(end)-UNIX_TIMESTAMP(start))
  )
);

mysql> select random_timestamp('2007-10-01', NOW());
+---------------------------------------+
| random_timestamp('2007-10-01', NOW()) |
+---------------------------------------+
| 2007-10-05 23:07:11                   |
+---------------------------------------+
1 row in set (0.00 sec)
New bloggers joining Open Sources: Zack, Savio and Dave D
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We're happy to announce that we have some new members of the Open Sources team of masked banditos. Zack Urlocker of MySQL Savio Rodrigues from IBM Dave Dargo, man of mystery and intrigue Zack started the ball rolling with a post on his recent trip to China.... READ MORE

Building an online business...online
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People are always surprised to find out just how distributed Alfresco is as an organization. Aside from a small hive in London, it's hard to find more than two Alfrescans in the same city. The same is largely true of MySQL and a number of new open source companies (MuleSource comes to mind). At Alfresco in the US, we have people in Austin, Boston, San Francisco, Denver, Salt Lake City, Atlanta, and New York City. Even where we have people in the same cities (there are now four of us in Salt Lake City), we don't have offices and only... READ MORE

Look who is coming to OSBC
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I just went through the attendee list for the Open Source Business Conference and loved what I saw. For the first time, OSBC is truly drawing a deep bench of IT buyers. It's something that we have strived for since the first show (well, the second, since the first show was intended to be a vendor strategy event), and which has finally happened. We have CIOs/VPs/Directors from the following companies (and I won't even bother to go into all the CXOs/VPs we have from Red Hat, MySQL, Alfresco, Microsoft, MuleSource, JasperSoft, SugarCRM, OpenBravo, Loopfuse, Zmanda, XenSource, etc. etc. - this... READ MORE

UK reaffirms its stance on software patents ("Yankee patent system, go home")
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The UK government yesterday re-affirmed its position on software patents: it doesn't like them, and won't enforce them.

The Government remains committed to its policy that no patents should exist for inventions which make advances lying solely in the field of software. Although certain jurisdictions, such as the US, allow more liberal patenting of software-based inventions, these patents cannot be enforced in the UK....

The Government will...continue to exclude patents from areas where they may hinder innovation: including patents which are too broad, speculative, or obvious, or where the advance they make lies in an excluded area such as software.

Stiff upper lift wins out in the end. Silliness continues to reign supreme here in the US regarding software patents.

Doing open source in the 'burbs
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I've suggested before that open source companies need not migrate to Silicon Valley. It's not really an open source question, though, so much as it is a persistent belief that to be big/important you must live in a big/important city.

The WSJ took on this topic in yesterday's Journal in an op-ed piece called "The Myth of 'Superstar' Cities." It begins:

These seem the best of times for America's elite cities. Wall Street's 2006 megabonuses created thousands of instant millionaires, and, with their venture-fund soulmates in places like San Francisco, Boston and Greenwich, the best people are prowling for Ferraris, planes, multimillion-dollar condos, the newest $200 lunch place and the

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Where the VC dollars go (geographically)
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From Paul Kedrosky:

Does this mean you should move to the Bay Area? Maybe. Plenty of open source companies have successfully grown outside the Valley (actually, the most successful ones - Red Hat, JBoss, MySQL), but it's certainly the case that there's more venture money in the Bay Area than anywhere else.

Of course, the primary VC complaint is having to get on a plane for board meetings, so maybe it's enough to do what Zend, MySQL, etc. have done: move management to the Bay Area. They may well be the only ones who can afford it. :-)

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The battle of the (closed) ecosystems (ZDNet)
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Josh Greenbaum at ZDNet suggests that the war of the ecosystems is on, and that Oracle is looking weak. I don't agree, but think Josh's commentary is interesting:

The partner front is the new flash point in the battle of the ecosystem. When it comes to IBM vs. Microsoft vs. SAP vs. Oracle, it turns out that a large coterie of happy, incented, and otherwise engaged partners that are out legitmizing an ecosystem vendor's ecosystem -? and selling the products and services they develop that fill in that ecosystem's white spaces - has become a major competitive weapon. And SAP is absolutely committed to making the most of this weapon in their four-way fight against their partner/competitors IBM, Oracle, and Microsoft.
True enough, though I think each of the big ecosystem vendors is missing out on the

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Infrastructure...important again
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I'm still reading through BusinessWeek's interview with Steve Ballmer, and still fascinated. Love him or hate him, Ballmer is a smart guy.

Ballmer refused to call the YouTube valuation ($1.65B) overvalued. He rightly said that it depends on a lot of factors (factors, incidentally, that I don't personally think add up, but I'm willing to be wrong):

You're clear as a bell on the YouTube valuation…
No. I'm not saying it is overvalued. I'm not trying to say that. It depends on a set of factors. I'm not saying I wouldn't write a check for that amount of money. I might.

Really, even though there's no identifiable business model?
It is one of those things where you have


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The other side of the "long tail"
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In case you missed its mention on Slashdot, the Financial Times has a funny (and telling) column today by James Boyle (Professor, Duke Law School) on the dark underbelly of the "long tail. You remember the long tail, right? It's manna from heaven - a chance for the Internet to enable a wider variety of sellers to find the wider variety of buyers than our previous markets have allowed.

Well, maybe life under the long tail isn't as rosy as life pontificating about the long tail, as Boyle discovers:

The academic in me has been very interested by the much hyped arrival of the “long tail” economy – the idea that the future lies in using the efficiency of the internet to sell smaller

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Distributing those billions
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Following on my "the winning mentality" post, here's a nice little image that Paul Kedrosky clued me into. It shows where the Forbes 400 richest Americans live - the billionaires, that is....

Soon enough, I'm expecting to see one dot in Alabama (Digium....), another few in California (SugarCRM, MySQL, etc.), and heck, let's give North Carolina a few more dollars, too.

Open source will crack the billion-dollar barrier, and a lot of people

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How I Work: Jason Gilmore, Open Source Editorial Director, Apress
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What is your role?
I'm the Open Source Editorial Director for Apress. I spend my days helping authors create great books, talking tech with some of the brightest guys in the computing industry, and travelling to various technical conferences around the country. I'm also the author of several books, and regularly contribute to various publications such as TechTarget's SearchOpenSource.com. My leisure time is spent working on various development projects and slowly remodeling my home.

What is your computer setup?
I use two laptops, one Windows XP and the second running Ubuntu. When working from my home office, I use dual monitors, the second being a 17" flat-panel Samsung. Using dual monitors is by far one of the greatest productivity gains I've ever encountered.

What desktop software applications do



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How I Work--what I have learned so far (send us your profile)
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I've spoken with all of the participants in our "How I Work" series and we're all having the same reaction. Not only is it cool to see how our peers do things, but you can actually put this stuff into practice. After reading Brian Akers' profile, I immediately started using OmniOutliner for my todo list. Now if only I could somehow sync it to a web interface...

All of us were surprised how many others use Macs and Treos. In fact, it seems that those who use Macs use Treos and those who use Windows lean towards BlackBerry. To that end, none of us have gotten a damn thing for free from either company. One of my Bschool chums works for Palm and thinks he can pry a 700p out of their coffers using the family discount, but not for free. I still can't believe Cingular and RIM haven't hit us up to test drive the 8700, which Peter was raving about and has made me rethink

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How I Work: Brian Aker, Dir. Architecture, MySQL
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What is your role?
My title is Director of Architecture, and in MySQL's history that has meant I have done everything from write code, assign bugs, handle operations for engineering, talk to customers, speak at conferences, and once help peel potatoes for dinner. Today I handle technical direction for MySQL, lead architects/senior engineers, and study how are market is evolving. I also still write code from time to time.

What is your computer setup?
I use a 15in PPC Apple Laptop.

What desktop software applications do you use daily?
When browsing I use Safari, but today I read far more RSS then I read web pages. For RSS I use an application called NewsFire. It allows me to scan all of my RSS headlines and select what I want to read. For some feeds I just use the spacebar to tab through all of the articles in the



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Showing entries 1 to 30 of 35 Next 5 Older Entries

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