Click here to close now.

Welcome!

XML Authors: Carmen Gonzalez, Jason Bloomberg, Pat Romanski, Andreas Grabner, Liz McMillan

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
Disruptive macro trends in technology are impacting and dramatically changing the "art of the possible" relative to supply chain management practices through the innovative use of IoT, cloud, machine learning and Big Data to enable connected ecosystems of engagement. Enterprise informatics can now move beyond point solutions that merely monitor the past and implement integrated enterprise fabrics that enable end-to-end supply chain visibility to improve customer service delivery and optimize supplier management. Learn about enterprise architecture strategies for designing connected systems tha...
Dale Kim is the Director of Industry Solutions at MapR. His background includes a variety of technical and management roles at information technology companies. While his experience includes work with relational databases, much of his career pertains to non-relational data in the areas of search, content management, and NoSQL, and includes senior roles in technical marketing, sales engineering, and support engineering. Dale holds an MBA from Santa Clara University, and a BA in Computer Science from the University of California, Berkeley.
Wearable devices have come of age. The primary applications of wearables so far have been "the Quantified Self" or the tracking of one's fitness and health status. We propose the evolution of wearables into social and emotional communication devices. Our BE(tm) sensor uses light to visualize the skin conductance response. Our sensors are very inexpensive and can be massively distributed to audiences or groups of any size, in order to gauge reactions to performances, video, or any kind of presentation. In her session at @ThingsExpo, Jocelyn Scheirer, CEO & Founder of Bionolux, will discuss ho...
The cloud is now a fact of life but generating recurring revenues that are driven by solutions and services on a consumption model have been hard to implement, until now. In their session at 16th Cloud Expo, Ermanno Bonifazi, CEO & Founder of Solgenia, and Ian Khan, Global Strategic Positioning & Brand Manager at Solgenia, will discuss how a top European telco has leveraged the innovative recurring revenue generating capability of the consumption cloud to enable a unique cloud monetization model to drive results.
As organizations shift toward IT-as-a-service models, the need for managing and protecting data residing across physical, virtual, and now cloud environments grows with it. CommVault can ensure protection &E-Discovery of your data – whether in a private cloud, a Service Provider delivered public cloud, or a hybrid cloud environment – across the heterogeneous enterprise. In his session at 16th Cloud Expo, Randy De Meno, Chief Technologist - Windows Products and Microsoft Partnerships, will discuss how to cut costs, scale easily, and unleash insight with CommVault Simpana software, the only si...
Analytics is the foundation of smart data and now, with the ability to run Hadoop directly on smart storage systems like Cloudian HyperStore, enterprises will gain huge business advantages in terms of scalability, efficiency and cost savings as they move closer to realizing the potential of the Internet of Things. In his session at 16th Cloud Expo, Paul Turner, technology evangelist and CMO at Cloudian, Inc., will discuss the revolutionary notion that the storage world is transitioning from mere Big Data to smart data. He will argue that today’s hybrid cloud storage solutions, with commodity...
Cloud data governance was previously an avoided function when cloud deployments were relatively small. With the rapid adoption in public cloud – both rogue and sanctioned, it’s not uncommon to find regulated data dumped into public cloud and unprotected. This is why enterprises and cloud providers alike need to embrace a cloud data governance function and map policies, processes and technology controls accordingly. In her session at 15th Cloud Expo, Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems, will focus on how to set up a cloud data governance program and s...
Every innovation or invention was originally a daydream. You like to imagine a “what-if” scenario. And with all the attention being paid to the so-called Internet of Things (IoT) you don’t have to stretch the imagination too much to see how this may impact commercial and homeowners insurance. We’re beyond the point of accepting this as a leap of faith. The groundwork is laid. Now it’s just a matter of time. We can thank the inventors of smart thermostats for developing a practical business application that everyone can relate to. Gone are the salad days of smart home apps, the early chalkb...
Roberto Medrano, Executive Vice President at SOA Software, had reached 30,000 page views on his home page - http://RobertoMedrano.SYS-CON.com/ - on the SYS-CON family of online magazines, which includes Cloud Computing Journal, Internet of Things Journal, Big Data Journal, and SOA World Magazine. He is a recognized executive in the information technology fields of SOA, internet security, governance, and compliance. He has extensive experience with both start-ups and large companies, having been involved at the beginning of four IT industries: EDA, Open Systems, Computer Security and now SOA.
The industrial software market has treated data with the mentality of “collect everything now, worry about how to use it later.” We now find ourselves buried in data, with the pervasive connectivity of the (Industrial) Internet of Things only piling on more numbers. There’s too much data and not enough information. In his session at @ThingsExpo, Bob Gates, Global Marketing Director, GE’s Intelligent Platforms business, to discuss how realizing the power of IoT, software developers are now focused on understanding how industrial data can create intelligence for industrial operations. Imagine ...
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...
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing and analyzing streaming data is the Lambda Architecture, representing a model of how to analyze rea...
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...
SYS-CON Events announced today that Vitria Technology, Inc. will exhibit at SYS-CON’s @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes for use cases across the industrial, enterprise, and consumer segments.
SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, 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. Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures traffic gets delivered faster, safer, and more reliably than ever.
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...
CommVault has announced that top industry technology visionaries have joined its leadership team. The addition of leaders from companies such as Oracle, SAP, Microsoft, Cisco, PwC and EMC signals the continuation of CommVault Next, the company's business transformation for sales, go-to-market strategies, pricing and packaging and technology innovation. The company also announced that it had realigned its structure to create business units to more directly match how customers evaluate, deploy, operate, and purchase technology.
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.
Performance is the intersection of power, agility, control, and choice. If you value performance, and more specifically consistent performance, you need to look beyond simple virtualized compute. Many factors need to be considered to create a truly performant environment. In his General Session at 15th Cloud Expo, Harold Hannon, Sr. Software Architect at SoftLayer, discussed how to take advantage of a multitude of compute options and platform features to make cloud the cornerstone of your online presence.
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...