Welcome!

XML Authors: Liz McMillan, Pat Romanski, Elizabeth White, Rick Delgado, Yeshim Deniz

Related Topics: XML, Open Source

XML: Article

eXist - An Introduction To Open Source Native XML Database

I am going to introduce you to the open source, free (GNU LGPL license), native XML database eXist (www.exist-db-org)

In this article I am going to introduce you to the open source, free (GNU LGPL license), native XML database eXist (www.exist-db-org). Data is important, no question about it. Data that can't be queried is not very useful. Users expect to have good query response time. From my personal experience and testing, I am confident in saying that eXist is a fairly good database. It has very good query response time, it is very user friendly, it's easy to set up and operate, and it's written in Java, therefore it is platform independent.

This article will show you how to use eXist as a stand-alone database server. If you have any problems or questions you can use the mailing list of eXist. The odds are somebody else had the same problem you have and it's already been answered in the mailing list.

Although eXist is written in Java, you don't have to be a Java programmer in order to use eXist. You can use the graphical user interface (GUI) for almost anything you need to accomplish. Anything that can be done through the GUI can also be done by using command line. This should please the programmers among us who are deeply attached to the command-line tools rather than fancy to GUIs. Let's start exploring eXist.

System Requirements
You need a JRE (Java Runtime Environment) 1.4 or later. This is the only requirement. The documentation states that the package is tested on Linux and Windows XP/2000. Keep in mind that it should work on other operating systems with no problem, because it's platform independent. I set it up on Dell PowerEdge 2600 running on Windows 2003 Server.

Features of eXist
eXist is a native XML database because it is designed and built for XML. Other databases, such as relational databases (Oracle, DB2, MS SQL Server 2000), can handle XML data too, but they are not native XML databases, because they aren't built for XML.

I will list only the most important features of eXist, but if you are interested, you can find a complete list of features at www.exist-db.org:

  • eXist supports many popular XML query languages such as XQuery, XPath, and XSLT
  • It has an automatic indexing features that lets it creates indexes while storing data
  • It supports data update
  • It supports SOAP and XML-RPC protocols
  • It doesn't support database transactions at this time, but it supports concurrent access
Step-by-Step Installation
1.  Get JVM (Java Virtual Machine)
If you don't have a JVM on your system already (1.4 or later), you should download one for free from Sun Microsystems (http://java.sun.com/j2se/). Make sure that your version is at least 1.4. As I write, the latest version of Java is 1.5.0_05 (also known as J2SE 5.0), which is I used for this article (see Figure 1).

2.  Set JAVA_HOME variable
The value of this variable is the full path to your Java installation directory. This is how I set up the JAVA_HOME environment variable on my system:

Control Panel->System->Advanced->Environment Variables->System Variables.

Next I created a new environment variable called "JAVA_HOME," with the value "C:\Program Files\Java\jdk1.5.0_05" (it may be different on your system).

To check if you set up the variable correctly, open a new command prompt window. Type "echo %JAVA_HOME%." You should see the Java installation directory printed on the screen (see Figure 2).

3.  Download eXist
You can download it from www.exist-db.org. For this article I used the most recent development snapshot: "eXist-snapshot-20050805.jar." (Note that the stable version eXist-1.0b2-build-1107.jar is referred to as "ancient." Interestingly enough, it still appears at the top of the list. Get the latest development version instead of the stable version.) (see Figure 3)

In order to run the installation program type:

java -jar eXist-snapshot-20050805.jar

That's it, we have installed it. Now you should see "eXist XML Database" entry in the Start->All Programs menu. Now you are ready to run eXist database server as a stand-alone application (see Figure 4).

Start eXist database server by selecting "eXist Database Startup" at the "eXist XML Database" program menu.

Let's start the client, the GUI that allows us to perform useful database operations such as querying the data and adding a file to or deleting a file from the database.

Start the client by selecting "eXist Client Shell" from the "eXist XML Database" program menu. For now the user "admin" who is the administrator doesn't have a password by default (I recommend creating a password for the admin as soon as possible). (see Figure 5)

Storing XML
Let's use the eXist client program to store XML data. Some of the things that the client program allows a user to do are:

  • create collections
  • store data
  • query data
  • create backup
  • restore files from backup
  • manage users
You should put related XML data under a collection. Just as for the file system, collections help organizing your data better. For example, if you have 100 XML orders, you should probably create an "Orders" collection and store all of the orders under this collection.

If you don't have suitable XML data at hand you use XBench, which is an XML benchmark (see the References section for more information). It comes with a random data generator and predefined set of queries. For this article I used a 10MB XML data file generated by XBench. You can download this data at www.cs.umb.edu/~smimarog/eXist/dictionary10.xml.

Follow these steps:

  • Download "dictionary10.xml" to your system.
  • Create a new collection using eXist client "File->Create Collection." Name it as XBench (see Figure 6). Now, you should see two collections: System and XBench (see Figure 7). The System collection is created by eXist at the installation, and it has system information.
  • Select XBench collection.
  • This collection is empty at the moment.
  • Select "File->Store files/directories." Browse and select "dictionary10.xml."
  • This will store the data. On my system it took less than a minute to store the data. This storage time varies, depending on your system.
Now that we have stored the data we are ready to query it. Note that while storing the data, eXist quietly created default indexes. Default indexes are generally enough for most purposes, but if you are willing to use eXist extensions, you can also create indexes manually, which will improve performance. Check the eXist documentation for details on this topic.

More Stories By Selim Mimaroglu

Selim Mimaroglu is a PhD candidate in computer science at the University of Massachusetts in Boston. He holds an MS in computer science from that school and has a BS in electrical engineering.

Comments (1) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
XML News Desk 11/29/05 07:22:28 PM EST

eXist - An Introduction To Open Source Native XML Database. In this article I am going to introduce you to the open source, free (GNU LGPL license), native XML database eXist (www.exist-db-org). Data is important, no question about it. Data that can't be queried is not very useful. Users expect to have good query response time. From my personal experience and testing, I am confident in saying that eXist is a fairly good database. It has very good query response time, it is very user friendly, it's easy to set up and operate, and it's written in Java, therefore it is platform independent.

@ThingsExpo Stories
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Nigeria has the largest economy in Africa, at more than US$500 billion, and ranks 23rd in the world. A recent re-evaluation of Nigeria's true economic size doubled the previous estimate, and brought it well ahead of South Africa, which is a member (unlike Nigeria) of the G20 club for political as well as economic reasons. Nigeria's economy can be said to be quite diverse from one point of view, but heavily dependent on oil and gas at the same time. Oil and natural gas account for about 15% of Nigera's overall economy, but traditionally represent more than 90% of the country's exports and as...
The Internet of Things is a misnomer. That implies that everything is on the Internet, and that simply should not be - especially for things that are blurring the line between medical devices that stimulate like a pacemaker and quantified self-sensors like a pedometer or pulse tracker. The mesh of things that we manage must be segmented into zones of trust for sensing data, transmitting data, receiving command and control administrative changes, and peer-to-peer mesh messaging. In his session at @ThingsExpo, Ryan Bagnulo, Solution Architect / Software Engineer at SOA Software, focused on desi...
"At our booth we are showing how to provide trust in the Internet of Things. Trust is where everything starts to become secure and trustworthy. Now with the scaling of the Internet of Things it becomes an interesting question – I've heard numbers from 200 billion devices next year up to a trillion in the next 10 to 15 years," explained Johannes Lintzen, Vice President of Sales at Utimaco, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
"For over 25 years we have been working with a lot of enterprise customers and we have seen how companies create applications. And now that we have moved to cloud computing, mobile, social and the Internet of Things, we see that the market needs a new way of creating applications," stated Jesse Shiah, CEO, President and Co-Founder of AgilePoint Inc., in this SYS-CON.tv interview at 15th Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that Gridstore™, the leader in hyper-converged infrastructure purpose-built to optimize Microsoft workloads, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Gridstore™ is the leader in hyper-converged infrastructure purpose-built for Microsoft workloads and designed to accelerate applications in virtualized environments. Gridstore’s hyper-converged infrastructure is the industry’s first all flash version of HyperConverged Appliances that include both compute and storag...
"People are a lot more knowledgeable about APIs now. There are two types of people who work with APIs - IT people who want to use APIs for something internal and the product managers who want to do something outside APIs for people to connect to them," explained Roberto Medrano, Executive Vice President at SOA Software, in this SYS-CON.tv interview at Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile devices as well as laptops and desktops using a visual drag-and-drop application – and eForms-buildi...
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
Code Halos - aka "digital fingerprints" - are the key organizing principle to understand a) how dumb things become smart and b) how to monetize this dynamic. In his session at @ThingsExpo, Robert Brown, AVP, Center for the Future of Work at Cognizant Technology Solutions, outlined research, analysis and recommendations from his recently published book on this phenomena on the way leading edge organizations like GE and Disney are unlocking the Internet of Things opportunity and what steps your organization should be taking to position itself for the next platform of digital competition.
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
As the Internet of Things unfolds, mobile and wearable devices are blurring the line between physical and digital, integrating ever more closely with our interests, our routines, our daily lives. Contextual computing and smart, sensor-equipped spaces bring the potential to walk through a world that recognizes us and responds accordingly. We become continuous transmitters and receivers of data. In his session at @ThingsExpo, Andrew Bolwell, Director of Innovation for HP's Printing and Personal Systems Group, discussed how key attributes of mobile technology – touch input, sensors, social, and ...
In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect at GE, and Ibrahim Gokcen, who leads GE's advanced IoT analytics, focused on the Internet of Things / Industrial Internet and how to make it operational for business end-users. Learn about the challenges posed by machine and sensor data and how to marry it with enterprise data. They also discussed the tips and tricks to provide the Industrial Internet as an end-user consumable service using Big Data Analytics and Industrial Cloud.
Building low-cost wearable devices can enhance the quality of our lives. In his session at Internet of @ThingsExpo, Sai Yamanoor, Embedded Software Engineer at Altschool, provided an example of putting together a small keychain within a $50 budget that educates the user about the air quality in their surroundings. He also provided examples such as building a wearable device that provides transit or recreational information. He then reviewed the resources available to build wearable devices at home including open source hardware, the raw materials required and the options available to power s...
Things are being built upon cloud foundations to transform organizations. This CEO Power Panel at 15th Cloud Expo, moderated by Roger Strukhoff, Cloud Expo and @ThingsExpo conference chair, addressed the big issues involving these technologies and, more important, the results they will achieve. Rodney Rogers, chairman and CEO of Virtustream; Brendan O'Brien, co-founder of Aria Systems, Bart Copeland, president and CEO of ActiveState Software; Jim Cowie, chief scientist at Dyn; Dave Wagstaff, VP and chief architect at BSQUARE Corporation; Seth Proctor, CTO of NuoDB, Inc.; and Andris Gailitis, C...
There's Big Data, then there's really Big Data from the Internet of Things. IoT is evolving to include many data possibilities like new types of event, log and network data. The volumes are enormous, generating tens of billions of logs per day, which raise data challenges. Early IoT deployments are relying heavily on both the cloud and managed service providers to navigate these challenges. In her session at Big Data Expo®, Hannah Smalltree, Director at Treasure Data, discussed how IoT, Big Data and deployments are processing massive data volumes from wearables, utilities and other machines...
"There is a natural synchronization between the business models, the IoT is there to support ,” explained Brendan O'Brien, Co-founder and Chief Architect of Aria Systems, in this SYS-CON.tv interview at the 15th International Cloud Expo®, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Media announced that Splunk, a provider of the leading software platform for real-time Operational Intelligence, has launched an ad campaign on Big Data Journal. Splunk software and cloud services enable organizations to search, monitor, analyze and visualize machine-generated big data coming from websites, applications, servers, networks, sensors and mobile devices. The ads focus on delivering ROI - how improved uptime delivered $6M in annual ROI, improving customer operations by mining large volumes of unstructured data, and how data tracking delivers uptime when it matters most.
In this Women in Technology Power Panel at 15th Cloud Expo, moderated by Anne Plese, Senior Consultant, Cloud Product Marketing at Verizon Enterprise, Esmeralda Swartz, CMO at MetraTech; Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems; Seema Jethani, Director of Product Management at Basho Technologies; Victoria Livschitz, CEO of Qubell Inc.; Anne Hungate, Senior Director of Software Quality at DIRECTV, discussed what path they took to find their spot within the technology industry and how do they see opportunities for other women in their area of expertise.
While great strides have been made relative to the video aspects of remote collaboration, audio technology has basically stagnated. Typically all audio is mixed to a single monaural stream and emanates from a single point, such as a speakerphone or a speaker associated with a video monitor. This leads to confusion and lack of understanding among participants especially regarding who is actually speaking. Spatial teleconferencing introduces the concept of acoustic spatial separation between conference participants in three dimensional space. This has been shown to significantly improve comprehe...