Introduction In this article, we are going to see how we can sort an SQL query result set using an ORDER BY clause that takes a RANDOM function provided by a database-specific function. This is a very handy trick, especially when you want to shuffle a given result set. Note that sorting a large result set using a RANDOM function might turn out to be very slow, so make sure you do that on small result sets. If you have to shuffle a large result set and limit it afterward, then it’s... Read More

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Working on a test case with sysbench, I encountered this:

mysql> select * from sbtest1 where id = round(rand()*10000, 0);
+------+--------+-------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------+
| id   | k      | c                                                                                                                       | pad                                                         |
+------+--------+-------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------+
|  179 | 499871 | 09833083632-34593445843-98203182724-77632394229-31240034691-22855093589-98577647071-95962909368-34814236148-76937610370 | 62233363025-41327474153-95482195752-11204169522-13131828192 |
| 1606 | 502031 | …

Nicolas Tobias has written an awesome guide to setting up replication from MariaDB to Hadoop/HDFS using Tungsten Replicator, in Spanish! He’s planning more of these so if you like what you see, please let him know!

Semana santa y yo con nuevas batallas que contar.
Me hayaba yo en el trabajo, pensando en que iba a invertir la calma que acompa;a a los dias de vacaciones que libremente podemos elegir trabajar y pense: No seria bueno terminar esa sincronizacion entre los servidores de mariaDB y HIVE?

Ya habia buscado algo de info al respecto en Enero hasta tenia una PoC montada con unas VM que volvi a encender, pero estaba todo podrido: no arrancaba, no funcionba ni siquiera me acordaba como lo habia hecho y el history de la shell er un galimatias. Decidi que si lo rehacia todo desde cero iba a poder dejarlo escrito en un playbook y ademas, aprenderlo y automatizarlo hasta el limite de poder desplegar de forma automatica on …

We all do need sometimes to generate raw valid dummy data for our use cases and applications as we start them. Obviously, one can write their own scripts to generate random data, but it is much better to have data, to which human beings can associate with like names, addresses instead of having them filled with random "lorem ipsum" string data :)

While searching for such a tool, I found a site which does exactly this: http://www.generatedata.com/

Documentation: http://benkeen.github.io/generatedata/

This can also be downloaded and installed locally. It supports three types of installations:
- A single, anonymous user account
- A single user account, requires login
- Multiple accounts

Below is the set of wide varied data types it supports for …

Generate useful test data and random dates in MySql. All code and tables are provided.

A short MySql function to generate a Lorum Ipsum text. You can download the code in the zip file below.

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

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 use to compare MySQL tools to  …

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.

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 […]