Whats new in Flexviews 1.6.0RC1

• This is the first release candidate before the final release.  If no major bugs are uncovered, then the next release will be the first GA release. 
• Flexviews now has a test suite for all major features.  The creation of these tests uncovered a number of issues which have been resolved in this release. 
• All MySQL aggregate functions except GROUP_CONCAT are now supported. 
• A special aggregate function called PERCENTILE is now also supported.  The calculation uses a modified version of the GROUP_CONCAT based solution suggested by Roland Bouman for percentiles.  This function should be considered experimental.  Please report bugs if you find any.
• You can add indexes to enabled materialized views using SQL_API/add_expr
• Adding PRIMARY KEY indexes is no longer …

I collect a lot of configuration values from my database servers and most of these values are stored by date.

So often I end up with values such as:


config_date config_value
2010-09-01  value_1
2010-09-02  value_1
2010-09-03  value_2
2010-09-04  value_3
2010-09-05  value_3
2010-09-06  value_3
2010-09-07  value_3
2010-09-08  value_4
2010-09-09  value_4
2010-09-10  value_1
2010-09-11  value_5
2010-09-12  value_5
2010-09-13  value_5
I´ve been unsuccessfully been trying to figure out how to convert this in SQL into something like the following:


config_from config_to   config_value
2010-09-01  2010-09-02  value_1
2010-09-03  2010-09-03  value_2
2010-09-04  2010-09-07 …

CouchDB is a document-oriented database written in Erlang that addresses a particular “sweet spot” in data storage and retrieval needs. This blog post is an introduction to CouchDB for those of us who have a relational database background.

A CouchDB database doesn’t have tables. It has a collection of documents, stored in a B+Tree. A document is a collection of attributes and values. Values can be atomic, or complex nested structures such as arrays and sub-documents. When you add a document to a database, CouchDB stores it in the B+Tree, indexed by two attributes with special meaning: _id and _rev.

CouchDB lets you store related data together even if it isn’t all the same type of data; you can store documents representing blog posts, users, and comments — all in the same database. This is not as chaotic as it sounds. To get your data back out of CouchDB in sensible ways, you define views over the database. A view stores a …

What data is available?

GEO data is expensive to create, so has been created by governments.  In the past governments charged for this data.  In 1980 the USGS was charging $300 (usd) per county for Oklahoma GEO data. (I complained to my congressman.) Today, a quick Internet search turns up lots of free GIS data.

I was hoping to find a neat collection of basic GEO data.   It would be nice if there was one place you could get world political borders (Polygons), postal codes (Polygons) and  points of interest like hospitals and airports.  What you can find is lots of  lists, often collections of odd data created for a virility of complex political purpose.  For example, The Global Change Master Directory is a large list of data sources on earth …

Recently, on our production servers we started seeing strange behavior by MySQL server while running queries on information_schema. Before getting into the gory details, I'd first explain the environment then the problem and its solution.

In this latest release I’ve added a basic MySQL connection pool to the benchmarking script which improves the method in which connections to MySQL are handled and reused. In addition, there have been some optimizations made to the thread handler functions for better debug reporting. Download the latest release now and see how your MySQL server performs against the rest of the community! Download here: download page.

Next year will mark a significant change for the MySQL community. At least three major conferences will have dedicated MySQL content that is great for attendees getting the best information on how to use MySQL from the experts in the field.

O’Reilly MySQL Conference & Expo

The 9th Annual MySQL conference will be held at is usual home of recent years. Colin will again be back as committee chair for a 3rd year and this will be my 6th straight MySQL conference.

Date: April 11 – 14, 2011
Location: Hyatt Regency, Santa Clara, California
Website: There is no website at this time
Call for Papers: There are no details for call for papers
Program Chairs: Colin Charles from Monty Program AB and Brian Aker.

Collaborate 11

…

I had an email after my webinar on NoSQL/SQL for Oracle Development Tools User Group last week (http://www.odtug.com/apex/f?p=500:1:0) from an attendee that was chock full of some questions. I decided to answer them to clarify with this fellow NoSQL and Cloud Systems. I'm pretty happy with my answers. I'd be glad for any thoughts from people about my replies.

Here are my responses (the fellow's name is also Patrick):

Patrick,

You are welcome! Thank you for attending. I put that together a bit hasty but thought it was a good topic to be covering as there are so many organizations that are considering such an architecture.

Patrick Francois wrote:
> Hi,
>
> Thank you for the NoSQL Webinar!
> Not an easy theme. ..kind of "wide open".
> I have recently also tried getting more …

I was recently struck by a problem which is unusual. In order to keep an eye on the database server I use nagios, cacti, merlin and some local scripts to monitor the database instance and ensure that it is working properly.  That normally works fine.  The different monitor processes do various things, one of which is to monitor the replication status of a slave, and warn me if the replication is not working or if it’s behind. This is done with the command SHOW SLAVE STATUS.

The server I was looking at runs some large local batch jobs aggregating data. Unfortunately, I was experiencing that replication was interfering with these batch jobs so decided to see if things would perform better if I stopped replication and let the batch …

Have you seen error messages similar to the following:

Communications link failure – Last packet sent to the server was X ms ago.

Judging from the forums, many people have had problems with this.  Here’s a brief overview of the causes, and potential solutions.

Generally speaking, this error suggests that the network connection has been closed. There can be several root causes:

• Firewalls or routers may clamp down on idle connections (the MySQL client/server protocol doesn’t ping).
• The MySQL Server may be closing idle …