In this article we will see one of the most interesting features added in Greenplum 4.2: XML datatype support. Introduction This article has an educational goal. Most likely you will not want to use the code presented here in a production system. However, it will give you hints and interesting ideas on how to add XML capabilities (both for loading and – most importantly – for searching) to your...

**External web tables** are one of the most useful features when you you have to load data into a Greenplum database from different sources. ## What is an external table? External web tables are a special type of external tables. The keyword *web* means that they are able to access dynamic data, and they can show it to you as if they were regular database tables. Given that data could change...

JDBC is the driver used to access a database with Java. Greenplum has a full working JDBC implementation. In this short article we’ll see how to use it. ## Download and install It is possible to download the JDBC for Greenplum directly from the Greenplum Community Edition site (http://www.greenplum.com/community/downloads/database-ce/). Look for the *”Connectivity Tools”* file. You will receive a...

With an announce on the forum, Greenplum staff has spoke out about the new version of their Database Management System. I can’t resist to blog about some of its new features. ## Cool new features You can find a [detailed summary of the new features on Greenplum’s website](http://www.greenplum.com/community/forums/showthread.php?565-Announcing-Greenplum-Databse-4.2). The first in the list is...

In the [previous article](https://www.2ndquadrant.com/en/2011/12/a-greenplum-41-handbook.html) we have seen how to install Greenplum on multiple nodes. After installation steps, we must init the entire system. Let’s see how. ## Actual situation If tou have followed previous article, you have a Greenplum installed on multiple nodes. Standar procedure when dealing with a Greenplum database, as well...

One of the main advantages using Greenplum is that it gains power when it uses multiple nodes. Horizontal scalability is a main feature of Greenplum. Here is a compact handbook to install a multi-node Data Warehouse environment with Greenplum. ## Preparation steps This little guide covers Greenplum 4.1 installation. This is not intended to be a replacement for the official Install Guide, just a...

Greenplum does not officially support Ubuntu Server 11.10 as underlying operating system. However, I needed to install it on the most recent Ubuntu server just to perform some tests and evaluate it. ## Some words on Ubuntu Server Ubuntu Server is increasing its popularity every day. Solutions like *Canonical Landcape* are getting more and more fans. In my case, I have to perform some tests with...

Through this article, we are going to complete the MapReduce job started in the [previous article](https://www.2ndquadrant.com/en/2011/10/mapreduce-in-greenplum.html). ## Take up the problem from the previous article In the [previous article](https://www.2ndquadrant.com/en/2011/10/mapreduce-in-greenplum.html), we left with this MapReduce configuration file: %YAML 1.1 --- VERSION: 1.0.0.1 DATABASE...

Mapreduce is a very trendy software framework. It has been introduced by Google (TM) in 2004. It is a large topic, and it is not possible to cover all of its aspetcs in a single blog article. This is a simple introduction to the _mapreduce_ usage in Greenplum 4.1. ## What is mapreduce exactly? Mapreduce’s main goal is to process highly distributable problems across huge datasets using a large...

In this article, I am going to upgrade a Greenplum cluster from version 4.0 to 4.1 using `gpmigrator`. `gpmigrator` is an utility shipped with Greenplum Community Edition whose purpose is to perform a live upgrade of an existing database. Requirements —————— In order for you to follow this article, you need a Greenplum 4.0 cluster up and running. I assume it has been installed in the standard path...